CVE-2026-68376: Linux kernel · sctp: fix auth_hmacs array size in struct sctp_cookie
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 8.1 High · fixed in ee5e65964f456adfe14d526fba0bd055de98ecf3 : patch Linux kernel soon.
Data as of 26 Oct 2026, 12:55 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 48% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Total control over the software or total information disclosure
CISA SSVC assessment, 2026-10-16.
- Patch
- Available – fixed in ee5e65964f456adfe14d526fba0bd055de98ecf3, e0b5252a59383b77d1b8dbeda00b7184dd95f4d3, d0a59ba58578e2b330fff80a44fe519f3ba7d8c7 +5
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 10 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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Description
In the Linux kernel, the following vulnerability has been resolved: sctp: fix auth_hmacs array size in struct sctp_cookie The auth_hmacs array in struct sctp_cookie is supposed to store a complete SCTP_AUTH_HMAC_ALGO parameter, which consists of a struct sctp_paramhdr followed by N HMAC identifiers. However, the array size was calculated using an extra 2 bytes instead of sizeof(struct sctp_paramhdr), which is 4 bytes. When four HMAC identifiers are configured, the HMAC-ALGO parameter stored in the endpoint is larger than the auth_hmacs buffer in the cookie. As a result, sctp_association_init() copies beyond the end of auth_hmacs when initializing the association, corrupting the adjacent auth_chunks field. This can lead to an invalid HMAC identifier being accepted and later cause an out-of-bounds read in sctp_auth_get_hmac(). Fix the array size calculation by including the full SCTP parameter header size.
References
- git.kernel.org/stable/c/317731d01b03c529809df36d3a7d149677a8729d (opens in a new tab)
- git.kernel.org/stable/c/0528485f27016a42804abe01aa61b39d85fa803e (opens in a new tab)
- git.kernel.org/stable/c/ee5e65964f456adfe14d526fba0bd055de98ecf3 (opens in a new tab)
- git.kernel.org/stable/c/0b4414e43e0861d67276031cc21401d7e87de3da (opens in a new tab)
- git.kernel.org/stable/c/d0a59ba58578e2b330fff80a44fe519f3ba7d8c7 (opens in a new tab)
- git.kernel.org/stable/c/a8d20ba0ab518c9ccbcde258f25fc1ee6e51d5db (opens in a new tab)
- git.kernel.org/stable/c/3aa40c3bccac2312ea7cf97f329190637f972b5d (opens in a new tab)
- git.kernel.org/stable/c/e0b5252a59383b77d1b8dbeda00b7184dd95f4d3 (opens in a new tab)