Vulnerability-Lookup

GHSA-734M-RP66-35Q4

Vulnerability from github – Published: 2026-07-19 12:30 – Updated: 2026-07-20 15:31

Details

In the Linux kernel, the following vulnerability has been resolved:

KEYS: fix overflow in keyctl_pkey_params_get_2()

The length for the internal output buffer is calculated incorrectly, which can result overflow when a too small buffer is provided.

Fix the bug by allocating internal output with the size of the maximum length of the cryptographic primitive instead of caller provided size.

Severity

7.8 (High)


                  
                    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2026-63824"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-787"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-19T12:16:55Z",
    "severity": "HIGH"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nKEYS: fix overflow in keyctl_pkey_params_get_2()\n\nThe length for the internal output buffer is calculated incorrectly, which\ncan result overflow when a too small buffer is provided.\n\nFix the bug by allocating internal output with the size of the maximum\nlength of the cryptographic primitive instead of caller provided size.",
  "id": "GHSA-734m-rp66-35q4",
  "modified": "2026-07-20T15:31:47Z",
  "published": "2026-07-19T12:30:24Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-63824"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0f3058d7d26f81df9b68a18ddbe164bdc3c5eff3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5165f1cc727f1322456735df212d8e26ec237a8d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5966e4e2ba213ab7ad559166152eb4f1f170dd2c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/622ec2dcd59f21623f2a7ab773c80ceb7d555e3a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/670fc6a311ed321522b7fff92cf0fc376b4f6e78"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b11c1fa32667692a2c0566e10163758e786e430c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b1e247338bc71826a2d2def3e0874c34749df69a"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/cb481e59ea6cae3b7796ac1d7a22b6b24c3f3c0b"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-63824 (GCVE-0-2026-63824)

Vulnerability from cvelistv5 – Published: 2026-07-19 12:02 – Updated: 2026-10-19 20:07

Title

KEYS: fix overflow in keyctl_pkey_params_get_2()

Summary

In the Linux kernel, the following vulnerability has been resolved: KEYS: fix overflow in keyctl_pkey_params_get_2() The length for the internal output buffer is calculated incorrectly, which can result overflow when a too small buffer is provided. Fix the bug by allocating internal output with the size of the maximum length of the cryptographic primitive instead of caller provided size.

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-10-16 15:31 UTC

CWE

CWE-787 - Out-of-bounds Write

Assigner

Linux CNA under the mitre root

CNA scorecard D 53/100 over 6992 records in the last 180 days details

References

8 references

URL	Tags
https://git.kernel.org/stable/c/622ec2dcd59f21623…
https://git.kernel.org/stable/c/b1e247338bc71826a…
https://git.kernel.org/stable/c/0f3058d7d26f81df9…
https://git.kernel.org/stable/c/5966e4e2ba213ab7a…
https://git.kernel.org/stable/c/5165f1cc727f13224…
https://git.kernel.org/stable/c/b11c1fa32667692a2…
https://git.kernel.org/stable/c/670fc6a311ed32152…
https://git.kernel.org/stable/c/cb481e59ea6cae3b7…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 00d60fd3b93219ea854220f0fd264b86398cbc53 , < 622ec2dcd59f21623f2a7ab773c80ceb7d555e3a (git) Affected: 00d60fd3b93219ea854220f0fd264b86398cbc53 , < b1e247338bc71826a2d2def3e0874c34749df69a (git) Affected: 00d60fd3b93219ea854220f0fd264b86398cbc53 , < 0f3058d7d26f81df9b68a18ddbe164bdc3c5eff3 (git) Affected: 00d60fd3b93219ea854220f0fd264b86398cbc53 , < 5966e4e2ba213ab7ad559166152eb4f1f170dd2c (git) Affected: 00d60fd3b93219ea854220f0fd264b86398cbc53 , < 5165f1cc727f1322456735df212d8e26ec237a8d (git) Affected: 00d60fd3b93219ea854220f0fd264b86398cbc53 , < b11c1fa32667692a2c0566e10163758e786e430c (git) Affected: 00d60fd3b93219ea854220f0fd264b86398cbc53 , < 670fc6a311ed321522b7fff92cf0fc376b4f6e78 (git) Affected: 00d60fd3b93219ea854220f0fd264b86398cbc53 , < cb481e59ea6cae3b7796ac1d7a22b6b24c3f3c0b (git)
Linux	Linux	Affected: 4.20 Unaffected: 0 , < 4.20 (semver) Unaffected: 5.10.260 , ≤ 5.10.* (semver) Unaffected: 5.15.211 , ≤ 5.15.* (semver) Unaffected: 6.1.177 , ≤ 6.1.* (semver) Unaffected: 6.6.144 , ≤ 6.6.* (semver) Unaffected: 6.12.95 , ≤ 6.12.* (semver) Unaffected: 6.18.38 , ≤ 6.18.* (semver) Unaffected: 7.1.3 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-63824",
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                "role": "CISA Coordinator",
                "timestamp": "2026-10-16T15:31:12.388673Z",
                "version": "2.0.3"
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              "status": "unaffected",
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              "value": "AV:L - The vulnerability is reachable only through the keyctl(2) syscall (KEYCTL_PKEY_ENCRYPT, KEYCTL_PKEY_DECRYPT, or KEYCTL_PKEY_SIGN); there is no network, adjacent, or physical attack path to the affected code.\nAC:L - An attacker fully controls the undersized out_len parameter and can reliably trigger the bug on demand with no races or victim-dependent state; CONFIG_ASYMMETRIC_KEY_TYPE is commonly enabled on server and desktop kernels.\nPR:L - Exploitation requires KEY_NEED_SEARCH on an asymmetric key, which any unprivileged local user can satisfy by loading their own RSA/EC key into a session keyring; no real root or init-namespace capabilities are needed.\nUI:N - Exploitation requires only attacker-initiated keyctl calls and does not depend on any victim user action such as opening a file or mounting a filesystem.\nS:U - Impact is confined to kernel heap memory corruption and privilege escalation within the same kernel security boundary; this is not a VM escape, sandbox escape, or cross-authority boundary violation.\nC:H - When out_len is smaller than the cryptographic output (including out_len=0 where kmalloc(0) yields ZERO_SIZE_PTR), asym_eds_op returns the full primitive output size and copy_to_user reads far beyond the allocated buffer, leaking adjacent kernel heap contents to userspace.\nI:H - The undersized kmalloc buffer is passed directly as the crypto output target; asymmetric operations can write up to the primitive maximum (hundreds of bytes for RSA-4096) past the allocation, enabling heap corruption and potential control-flow hijacking.\nA:H - Heap out-of-bounds read/write against kmalloc objects or writes through ZERO_SIZE_PTR can cause kernel oops, panic, or KASAN-detected corruption, satisfying high availability impact."
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

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