CWE-444
AllowedInconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Abstraction: Base · Status: Incomplete
The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.
625 vulnerabilities reference this CWE, most recent first.
GHSA-694Q-MQC8-23W4
Vulnerability from github – Published: 2022-05-14 02:41 – Updated: 2022-05-14 02:41HPE has identified a remote HOST header attack vulnerability in HPE CentralView Fraud Risk Management earlier than version CV 6.1. This issue is resolved in HF16 for HPE CV 6.1 or subsequent version.
{
"affected": [],
"aliases": [
"CVE-2018-7068"
],
"database_specific": {
"cwe_ids": [
"CWE-444"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2018-08-06T20:29:00Z",
"severity": "MODERATE"
},
"details": "HPE has identified a remote HOST header attack vulnerability in HPE CentralView Fraud Risk Management earlier than version CV 6.1. This issue is resolved in HF16 for HPE CV 6.1 or subsequent version.",
"id": "GHSA-694q-mqc8-23w4",
"modified": "2022-05-14T02:41:32Z",
"published": "2022-05-14T02:41:32Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2018-7068"
},
{
"type": "WEB",
"url": "https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US\u0026docId=emr_na-hpesbmu03837en_us"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-69F9-5GXW-WVC2
Vulnerability from github – Published: 2026-01-05 22:58 – Updated: 2026-01-06 16:06Summary
The Python HTTP parser may allow a request smuggling attack with the presence of non-ASCII characters.
Impact
If a pure Python version of aiohttp is installed (i.e. without the usual C extensions) or AIOHTTP_NO_EXTENSIONS is enabled, then an attacker may be able to execute a request smuggling attack to bypass certain firewalls or proxy protections.
Patch: https://github.com/aio-libs/aiohttp/commit/32677f2adfd907420c078dda6b79225c6f4ebce0
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 3.13.2"
},
"package": {
"ecosystem": "PyPI",
"name": "aiohttp"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "3.13.3"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2025-69224"
],
"database_specific": {
"cwe_ids": [
"CWE-444"
],
"github_reviewed": true,
"github_reviewed_at": "2026-01-05T22:58:57Z",
"nvd_published_at": "2026-01-05T23:15:40Z",
"severity": "LOW"
},
"details": "### Summary\nThe Python HTTP parser may allow a request smuggling attack with the presence of non-ASCII characters.\n\n### Impact\nIf a pure Python version of aiohttp is installed (i.e. without the usual C extensions) or AIOHTTP_NO_EXTENSIONS is enabled, then an attacker may be able to execute a request smuggling attack to bypass certain firewalls or proxy protections.\n\n------\n\nPatch: https://github.com/aio-libs/aiohttp/commit/32677f2adfd907420c078dda6b79225c6f4ebce0",
"id": "GHSA-69f9-5gxw-wvc2",
"modified": "2026-01-06T16:06:40Z",
"published": "2026-01-05T22:58:57Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/aio-libs/aiohttp/security/advisories/GHSA-69f9-5gxw-wvc2"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-69224"
},
{
"type": "WEB",
"url": "https://github.com/aio-libs/aiohttp/commit/32677f2adfd907420c078dda6b79225c6f4ebce0"
},
{
"type": "PACKAGE",
"url": "https://github.com/aio-libs/aiohttp"
}
],
"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/E:U",
"type": "CVSS_V4"
}
],
"summary": "AIOHTTP\u0027s unicode processing of header values could cause parsing discrepancies"
}
GHSA-6F62-3596-G6W7
Vulnerability from github – Published: 2024-09-22 03:30 – Updated: 2024-09-25 17:53An issue was discovered in the WEBrick toolkit through 1.8.1 for Ruby. It allows HTTP request smuggling by providing both a Content-Length header and a Transfer-Encoding header, e.g., "GET /admin HTTP/1.1\r\n" inside of a "POST /user HTTP/1.1\r\n" request. NOTE: the supplier's position is "Webrick should not be used in production."
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 1.8.1"
},
"package": {
"ecosystem": "RubyGems",
"name": "webrick"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "1.8.2"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2024-47220"
],
"database_specific": {
"cwe_ids": [
"CWE-444"
],
"github_reviewed": true,
"github_reviewed_at": "2024-09-23T20:43:55Z",
"nvd_published_at": "2024-09-22T01:15:11Z",
"severity": "HIGH"
},
"details": "An issue was discovered in the WEBrick toolkit through 1.8.1 for Ruby. It allows HTTP request smuggling by providing both a Content-Length header and a Transfer-Encoding header, e.g., \"GET /admin HTTP/1.1\\r\\n\" inside of a \"POST /user HTTP/1.1\\r\\n\" request. NOTE: the supplier\u0027s position is \"Webrick should not be used in production.\"",
"id": "GHSA-6f62-3596-g6w7",
"modified": "2024-09-25T17:53:10Z",
"published": "2024-09-22T03:30:30Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2024-47220"
},
{
"type": "WEB",
"url": "https://github.com/ruby/webrick/issues/145"
},
{
"type": "WEB",
"url": "https://github.com/ruby/webrick/issues/145#issuecomment-2369994610"
},
{
"type": "WEB",
"url": "https://github.com/ruby/webrick/issues/145#issuecomment-2372838285"
},
{
"type": "WEB",
"url": "https://github.com/ruby/webrick/pull/146/commits/d88321da45dcd230ac2b4585cad4833d6d5e8841"
},
{
"type": "WEB",
"url": "https://github.com/ruby/webrick/commit/f5faca9222541591e1a7c3c97552ebb0c92733c7"
},
{
"type": "PACKAGE",
"url": "https://github.com/ruby/webrick"
},
{
"type": "WEB",
"url": "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/webrick/CVE-2024-47220.yml"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
"type": "CVSS_V3"
}
],
"summary": "HTTP Request Smuggling in ruby webrick"
}
GHSA-6GPV-F676-PRM8
Vulnerability from github – Published: 2022-05-24 17:12 – Updated: 2022-10-07 00:00There is a vulnerability in Apache Traffic Server 6.0.0 to 6.2.3, 7.0.0 to 7.1.8, and 8.0.0 to 8.0.5 with a smuggling attack and Transfer-Encoding and Content length headers. Upgrade to versions 7.1.9 and 8.0.6 or later versions.
{
"affected": [],
"aliases": [
"CVE-2020-1944"
],
"database_specific": {
"cwe_ids": [
"CWE-444"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2020-03-23T22:15:00Z",
"severity": "HIGH"
},
"details": "There is a vulnerability in Apache Traffic Server 6.0.0 to 6.2.3, 7.0.0 to 7.1.8, and 8.0.0 to 8.0.5 with a smuggling attack and Transfer-Encoding and Content length headers. Upgrade to versions 7.1.9 and 8.0.6 or later versions.",
"id": "GHSA-6gpv-f676-prm8",
"modified": "2022-10-07T00:00:52Z",
"published": "2022-05-24T17:12:33Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2020-1944"
},
{
"type": "WEB",
"url": "https://lists.apache.org/thread.html/r99d18d0bc4daa05e7d0e5a63e0e22701a421b2ef5a8f4f7694c43869%40%3Cannounce.trafficserver.apache.org%3E"
},
{
"type": "WEB",
"url": "https://www.debian.org/security/2020/dsa-4672"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-6HC3-539H-6XC6
Vulnerability from github – Published: 2022-02-11 00:00 – Updated: 2025-10-22 00:32SAP NetWeaver Application Server ABAP, SAP NetWeaver Application Server Java, ABAP Platform, SAP Content Server 7.53 and SAP Web Dispatcher are vulnerable for request smuggling and request concatenation. An unauthenticated attacker can prepend a victim's request with arbitrary data. This way, the attacker can execute functions impersonating the victim or poison intermediary Web caches. A successful attack could result in complete compromise of Confidentiality, Integrity and Availability of the system.
{
"affected": [],
"aliases": [
"CVE-2022-22536"
],
"database_specific": {
"cwe_ids": [
"CWE-444"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2022-02-09T23:15:00Z",
"severity": "CRITICAL"
},
"details": "SAP NetWeaver Application Server ABAP, SAP NetWeaver Application Server Java, ABAP Platform, SAP Content Server 7.53 and SAP Web Dispatcher are vulnerable for request smuggling and request concatenation. An unauthenticated attacker can prepend a victim\u0027s request with arbitrary data. This way, the attacker can execute functions impersonating the victim or poison intermediary Web caches. A successful attack could result in complete compromise of Confidentiality, Integrity and Availability of the system.",
"id": "GHSA-6hc3-539h-6xc6",
"modified": "2025-10-22T00:32:29Z",
"published": "2022-02-11T00:00:50Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2022-22536"
},
{
"type": "WEB",
"url": "https://launchpad.support.sap.com/#/notes/3123396"
},
{
"type": "WEB",
"url": "https://wiki.scn.sap.com/wiki/display/PSR/SAP+Security+Patch+Day+-+February+2022"
},
{
"type": "WEB",
"url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2022-22536"
},
{
"type": "WEB",
"url": "https://www.sap.com/documents/2022/02/fa865ea4-167e-0010-bca6-c68f7e60039b.html"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H",
"type": "CVSS_V3"
}
]
}
GHSA-6HFF-9F4H-85XM
Vulnerability from github – Published: 2026-08-04 03:31 – Updated: 2026-08-04 03:31A flaw in Node.js HTTP client can cause a request desynchronization for Node.js-based forwarding proxies that rebuild outbound headers from the visible IncomingMessage headers while piping the original body to a reused backend connection.
Node.js can omit headers beyond maxHeadersCount / maxHeaderPairs from req.headers, req.rawHeaders, and req.headersDistinct, while still using those omitted headers internally for HTTP message framing. In particular, Content-Length can be hidden from userland while the request body is still delivered.
This vulnerability affects all supported release lines: Node.js 22, Node.js 24, and Node.js 26.
{
"affected": [],
"aliases": [
"CVE-2026-58044"
],
"database_specific": {
"cwe_ids": [
"CWE-444"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-08-04T01:16:20Z",
"severity": "LOW"
},
"details": "A flaw in Node.js HTTP client can cause a request desynchronization for Node.js-based forwarding proxies that rebuild outbound headers from the visible `IncomingMessage` headers while piping the original body to a reused backend connection.\n\nNode.js can omit headers beyond `maxHeadersCount` / `maxHeaderPairs` from `req.headers`, `req.rawHeaders`, and `req.headersDistinct`, while still using those omitted headers internally for HTTP message framing. In particular, `Content-Length` can be hidden from userland while the request body is still delivered.\n\nThis vulnerability affects all supported release lines: **Node.js 22**, **Node.js 24**, and **Node.js 26**.",
"id": "GHSA-6hff-9f4h-85xm",
"modified": "2026-08-04T03:31:10Z",
"published": "2026-08-04T03:31:10Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-58044"
},
{
"type": "WEB",
"url": "https://nodejs.org/en/blog/vulnerability/july-2026-security-releases"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N",
"type": "CVSS_V3"
}
]
}
GHSA-6HFQ-H8HQ-87MF
Vulnerability from github – Published: 2021-08-25 20:56 – Updated: 2021-08-18 21:07Summary
hyper's HTTP server code had a flaw that incorrectly understands some requests with multiple transfer-encoding headers to have a chunked payload, when it should have been rejected as illegal. This combined with an upstream HTTP proxy that understands the request payload boundary differently can result in "request smuggling" or "desync attacks".
Vulnerability
The flaw was introduced in https://github.com/hyperium/hyper/commit/26417fc24a7d05df538e0f39239b373c5c3d61f6, released in v0.12.0.
Consider this example request:
POST /yolo HTTP/1.1
Transfer-Encoding: chunked
Transfer-Encoding: cow
This request should be rejected, according to RFC 7230, since it has a Transfer-Encoding header, but after folding, it does not end in chunked. hyper would notice the chunked in the first line, and then check the second line, and thanks to a missing boolean assignment, not set the error condition. hyper would treat the payload as being chunked. By differing from the spec, it is possible to send requests like these to endpoints that have different HTTP implementations, with different interpretations of the payload semantics, and cause "desync attacks".
There are several parts of the spec that must also be checked, and hyper correctly handles all of those. Additionally, hyper's client does not allow sending requests with improper headers, so the misunderstanding cannot be propagated further.
Read more about desync attacks: https://portswigger.net/research/http-desync-attacks-request-smuggling-reborn
Impact
To determine if vulnerable, all these things must be true:
- Using hyper as an HTTP server. The client is not affected.
- Using HTTP/1.1. HTTP/2 does not use
transfer-encoding. - Using a vulnerable HTTP proxy upstream to hyper. If an upstream proxy correctly rejects the illegal transfer-encoding headers, the desync attack cannot succeed. If there is no proxy upstream of hyper, hyper cannot start the desync attack, as the client will repair the headers before forwarding.
Patches
We have released and backported the following patch versions:
- v0.14.3
- v0.13.10
Workarounds
Besides upgrading hyper, you can take the following options:
- Reject requests that contain a
transfer-encodingheader. - Ensure any upstream proxy handles
transfer-encodingcorrectly.
Credits
This issue was initially reported by ZeddYu Lu From Qi An Xin Technology Research Institute.
{
"affected": [
{
"package": {
"ecosystem": "crates.io",
"name": "hyper"
},
"ranges": [
{
"events": [
{
"introduced": "0.14.0"
},
{
"fixed": "0.14.3"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "crates.io",
"name": "hyper"
},
"ranges": [
{
"events": [
{
"introduced": "0.13.0"
},
{
"fixed": "0.13.10"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "crates.io",
"name": "hyper"
},
"ranges": [
{
"events": [
{
"introduced": "0.12.0"
},
{
"fixed": "0.12.36"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2021-21299"
],
"database_specific": {
"cwe_ids": [
"CWE-444"
],
"github_reviewed": true,
"github_reviewed_at": "2021-08-18T21:07:17Z",
"nvd_published_at": null,
"severity": "MODERATE"
},
"details": "### Summary\n\nhyper\u0027s HTTP server code had a flaw that incorrectly understands some requests with multiple transfer-encoding headers to have a chunked payload, when it should have been rejected as illegal. This combined with an upstream HTTP proxy that understands the request payload boundary differently can result in \"request smuggling\" or \"desync attacks\".\n\n### Vulnerability\n\nThe flaw was introduced in https://github.com/hyperium/hyper/commit/26417fc24a7d05df538e0f39239b373c5c3d61f6, released in v0.12.0.\n\nConsider this example request:\n\n```\nPOST /yolo HTTP/1.1\nTransfer-Encoding: chunked\nTransfer-Encoding: cow\n```\n\nThis request *should* be rejected, according to RFC 7230, since it has a `Transfer-Encoding` header, but after folding, it does not end in `chunked`. hyper would notice the `chunked` in the first line, and then check the second line, and thanks to a missing boolean assignment, *not* set the error condition. hyper would treat the payload as being `chunked`. By differing from the spec, it is possible to send requests like these to endpoints that have different HTTP implementations, with different interpretations of the payload semantics, and cause \"desync attacks\".\n\nThere are several parts of the spec that must also be checked, and hyper correctly handles all of those. Additionally, hyper\u0027s *client* does not allow sending requests with improper headers, so the misunderstanding cannot be propagated further.\n\nRead more about desync attacks: https://portswigger.net/research/http-desync-attacks-request-smuggling-reborn\n\n### Impact\n\nTo determine if vulnerable, all these things must be true:\n\n- **Using hyper as an HTTP *server*.** The client is not affected.\n- **Using HTTP/1.1.** HTTP/2 does not use `transfer-encoding`.\n- **Using a vulnerable HTTP proxy upstream to hyper.** If an upstream proxy correctly rejects the illegal transfer-encoding headers, the desync attack cannot succeed. If there is *no* proxy upstream of hyper, hyper cannot *start* the desync attack, as the client will repair the headers before forwarding.\n\n### Patches\n\nWe have released and backported the following patch versions:\n\n- v0.14.3\n- v0.13.10\n\n### Workarounds\n\nBesides upgrading hyper, you can take the following options:\n\n- Reject requests that contain a `transfer-encoding` header.\n- Ensure any upstream proxy handles `transfer-encoding` correctly.\n\n### Credits\n\nThis issue was initially reported by ZeddYu Lu From Qi An Xin Technology Research Institute.",
"id": "GHSA-6hfq-h8hq-87mf",
"modified": "2021-08-18T21:07:17Z",
"published": "2021-08-25T20:56:18Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/hyperium/hyper/security/advisories/GHSA-6hfq-h8hq-87mf"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2021-21299"
},
{
"type": "WEB",
"url": "https://github.com/hyperium/hyper/commit/8f93123efef5c1361086688fe4f34c83c89cec02"
},
{
"type": "PACKAGE",
"url": "https://github.com/hyperium/hyper"
},
{
"type": "WEB",
"url": "https://portswigger.net/research/http-desync-attacks-request-smuggling-reborn"
},
{
"type": "WEB",
"url": "https://rustsec.org/advisories/RUSTSEC-2021-0020.html"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "HTTP Request Smuggling in hyper"
}
GHSA-6HR6-W5QG-QMWG
Vulnerability from github – Published: 2026-08-06 21:53 – Updated: 2026-08-06 21:53Impact
h2 <=4.4.0 accepts request header blocks containing more than one Host header, and forwards every Host header to the consuming application. Where the consumer downgrades HTTP/2 to HTTP/1.1, the resulting request carries two Host header lines, which is a request smuggling primitive (CWE-444).
Patches
Patched and fixed in v4.4.1
Workarounds
Users of the h2 library are advised to check and follow HTTP semantics best practices in their application code. h2 provides best effort sanity checks, but ultimately the calling code is responsible to ensure proper and safe usage of HTTP/2 as provided by h2, hyperframe, and hpack.
References
Similar to the previously disclosed and fixed duplicate content-length issue.
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 4.4.0"
},
"package": {
"ecosystem": "PyPI",
"name": "h2"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "4.4.1"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-71554"
],
"database_specific": {
"cwe_ids": [
"CWE-444"
],
"github_reviewed": true,
"github_reviewed_at": "2026-08-06T21:53:41Z",
"nvd_published_at": null,
"severity": "MODERATE"
},
"details": "### Impact\nh2 \u003c=4.4.0 accepts request header blocks containing more than one Host header, and forwards every Host header to the consuming application. Where the consumer downgrades HTTP/2 to HTTP/1.1, the resulting request carries two Host header lines, which is a request smuggling primitive (CWE-444).\n\n### Patches\nPatched and fixed in v4.4.1\n\n### Workarounds\nUsers of the h2 library are advised to check and follow HTTP semantics best practices in their application code. h2 provides best effort sanity checks, but ultimately the calling code is responsible to ensure proper and safe usage of HTTP/2 as provided by h2, hyperframe, and hpack.\n\n### References\nSimilar to the previously disclosed and fixed duplicate content-length issue.",
"id": "GHSA-6hr6-w5qg-qmwg",
"modified": "2026-08-06T21:53:41Z",
"published": "2026-08-06T21:53:41Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/python-hyper/h2/security/advisories/GHSA-6hr6-w5qg-qmwg"
},
{
"type": "WEB",
"url": "https://github.com/python-hyper/h2/commit/292a40829feefda98c8509dcdbbb4a57af9bd6a6"
},
{
"type": "PACKAGE",
"url": "https://github.com/python-hyper/h2"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
"type": "CVSS_V3"
}
],
"summary": "h2: Duplicate Host header could facilitate request smuggling"
}
GHSA-6J2Q-C73V-97C5
Vulnerability from github – Published: 2025-05-30 06:30 – Updated: 2025-07-28 20:34Spring Cloud Gateway Server forwards the X-Forwarded-For and Forwarded headers from untrusted proxies.
{
"affected": [
{
"package": {
"ecosystem": "Maven",
"name": "org.springframework.cloud:spring-cloud-gateway-server"
},
"ranges": [
{
"events": [
{
"introduced": "4.2.0"
},
{
"fixed": "4.2.3"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Maven",
"name": "org.springframework.cloud:spring-cloud-gateway-server"
},
"ranges": [
{
"events": [
{
"introduced": "4.1.0"
},
{
"fixed": "4.1.8"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Maven",
"name": "org.springframework.cloud:spring-cloud-gateway-server"
},
"ranges": [
{
"events": [
{
"introduced": "4.0.0"
},
{
"last_affected": "4.0.9"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Maven",
"name": "org.springframework.cloud:spring-cloud-gateway-server"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "3.1.10"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Maven",
"name": "org.springframework.cloud:spring-cloud-gateway-server-mvc"
},
"ranges": [
{
"events": [
{
"introduced": "4.1.7"
},
{
"fixed": "4.2.3"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2025-41235"
],
"database_specific": {
"cwe_ids": [
"CWE-444"
],
"github_reviewed": true,
"github_reviewed_at": "2025-05-30T15:25:10Z",
"nvd_published_at": "2025-05-30T06:15:26Z",
"severity": "HIGH"
},
"details": "Spring Cloud Gateway Server forwards the X-Forwarded-For\u00a0and Forwarded\u00a0headers from untrusted proxies.",
"id": "GHSA-6j2q-c73v-97c5",
"modified": "2025-07-28T20:34:06Z",
"published": "2025-05-30T06:30:25Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-41235"
},
{
"type": "PACKAGE",
"url": "https://github.com/spring-cloud/spring-cloud-gateway"
},
{
"type": "WEB",
"url": "https://spring.io/security/cve-2025-41235"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N",
"type": "CVSS_V3"
}
],
"summary": "Spring Cloud Gateway Server Forwards Headers from Untrusted Proxies"
}
GHSA-6JV3-5F52-599M
Vulnerability from github – Published: 2026-06-15 20:22 – Updated: 2026-06-15 20:22Summary
QuerystringParser treated ; as a field separator in application/x-www-form-urlencoded bodies, in addition to &. The WHATWG URL standard, modern browsers, and Python's urllib.parse (since the CVE-2021-23336 fix) treat only & as a separator. This creates a parser differential: the same bytes are tokenized into different fields than a WHATWG compliant intermediary would produce, allowing an attacker to smuggle extra form fields past an upstream body inspecting component.
Details
In python_multipart/multipart.py, the FIELD_NAME and FIELD_DATA states located the next separator by scanning for & and, failing that, for ;:
sep_pos = data.find(b"&", i)
if sep_pos == -1:
sep_pos = data.find(b";", i)
As a result, ; acted as a field boundary. Because the fallback only triggered when no & remained in the current chunk, tokenization also depended on unrelated bytes later in the buffer and on how the body was split across write() calls. This is the same class of issue as CVE-2021-23336 in CPython's urllib.parse.
For example, a body inspecting WAF or gateway that follows the WHATWG rule (only & separates fields) receives:
role=user&x=;role=admin
The upstream parses two fields, role=user and x=";role=admin", sees a benign role=user, and forwards the request. QuerystringParser parsed the same bytes as three fields: role="user", x="", and role="admin". The application (for example via Starlette/FastAPI request.form(), where the last value wins) then received role=admin, a value the upstream validator never saw.
The parser is reachable through the public QuerystringParser class, the high level FormParser, create_form_parser, and parse_form APIs, and Starlette/FastAPI request.form() for url encoded bodies.
Impact
Interpretation conflict / HTTP parameter pollution. An attacker can smuggle extra or overriding form fields past an upstream component that applies the WHATWG separator rule, reaching the backend with parameters the intermediary did not observe.
Mitigation
Upgrade to python-multipart 0.0.30 or later, which treats only & as a field separator per the WHATWG URL standard. ; is parsed as ordinary field data, matching urllib.parse, browsers, and other compliant parsers.
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "python-multipart"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "0.0.30"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-53538"
],
"database_specific": {
"cwe_ids": [
"CWE-436",
"CWE-444"
],
"github_reviewed": true,
"github_reviewed_at": "2026-06-15T20:22:25Z",
"nvd_published_at": null,
"severity": "LOW"
},
"details": "### Summary\n\n`QuerystringParser` treated `;` as a field separator in `application/x-www-form-urlencoded` bodies, in addition to `\u0026`. The [WHATWG URL standard](https://url.spec.whatwg.org/#urlencoded-parsing), modern browsers, and Python\u0027s `urllib.parse` (since the CVE-2021-23336 fix) treat only `\u0026` as a separator. This creates a parser differential: the same bytes are tokenized into different fields than a WHATWG compliant intermediary would produce, allowing an attacker to smuggle extra form fields past an upstream body inspecting component.\n\n### Details\n\nIn `python_multipart/multipart.py`, the `FIELD_NAME` and `FIELD_DATA` states located the next separator by scanning for `\u0026` and, failing that, for `;`:\n\n```python\nsep_pos = data.find(b\"\u0026\", i)\nif sep_pos == -1:\n sep_pos = data.find(b\";\", i)\n```\n\nAs a result, `;` acted as a field boundary. Because the fallback only triggered when no `\u0026` remained in the current chunk, tokenization also depended on unrelated bytes later in the buffer and on how the body was split across `write()` calls. This is the same class of issue as CVE-2021-23336 in CPython\u0027s `urllib.parse`.\n\nFor example, a body inspecting WAF or gateway that follows the WHATWG rule (only `\u0026` separates fields) receives:\n\n```\nrole=user\u0026x=;role=admin\n```\n\nThe upstream parses two fields, `role=user` and `x=\";role=admin\"`, sees a benign `role=user`, and forwards the request. `QuerystringParser` parsed the same bytes as three fields: `role=\"user\"`, `x=\"\"`, and `role=\"admin\"`. The application (for example via Starlette/FastAPI `request.form()`, where the last value wins) then received `role=admin`, a value the upstream validator never saw.\n\nThe parser is reachable through the public `QuerystringParser` class, the high level `FormParser`, `create_form_parser`, and `parse_form` APIs, and Starlette/FastAPI `request.form()` for url encoded bodies.\n\n### Impact\n\nInterpretation conflict / HTTP parameter pollution. An attacker can smuggle extra or overriding form fields past an upstream component that applies the WHATWG separator rule, reaching the backend with parameters the intermediary did not observe.\n\n### Mitigation\n\nUpgrade to `python-multipart` `0.0.30` or later, which treats only `\u0026` as a field separator per the [WHATWG URL standard](https://url.spec.whatwg.org/#urlencoded-parsing). `;` is parsed as ordinary field data, matching `urllib.parse`, browsers, and other compliant parsers.",
"id": "GHSA-6jv3-5f52-599m",
"modified": "2026-06-15T20:22:25Z",
"published": "2026-06-15T20:22:25Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/Kludex/python-multipart/security/advisories/GHSA-6jv3-5f52-599m"
},
{
"type": "PACKAGE",
"url": "https://github.com/Kludex/python-multipart"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "python-multipart: Semicolon treated as querystring field separator enables parameter smuggling"
}
Mitigation
Use a web server that employs a strict HTTP parsing procedure, such as Apache [REF-433].
Mitigation
Use only SSL communication.
Mitigation
Terminate the client session after each request.
Mitigation
Turn all pages to non-cacheable.
CAPEC-273: HTTP Response Smuggling
An adversary manipulates and injects malicious content in the form of secret unauthorized HTTP responses, into a single HTTP response from a vulnerable or compromised back-end HTTP agent (e.g., server).
See CanPrecede relationships for possible consequences.
CAPEC-33: HTTP Request Smuggling
An adversary abuses the flexibility and discrepancies in the parsing and interpretation of HTTP Request messages using various HTTP headers, request-line and body parameters as well as message sizes (denoted by the end of message signaled by a given HTTP header) by different intermediary HTTP agents (e.g., load balancer, reverse proxy, web caching proxies, application firewalls, etc.) to secretly send unauthorized and malicious HTTP requests to a back-end HTTP agent (e.g., web server).
See CanPrecede relationships for possible consequences.