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CVE-2026-53246 (GCVE-0-2026-53246)

Vulnerability from cvelistv5 – Published: 2026-06-25 08:39 – Updated: 2026-08-05 12:34
VLAI
Title
sctp: validate cached peer INIT chunk length in COOKIE_ECHO processing
Summary
In the Linux kernel, the following vulnerability has been resolved: sctp: validate cached peer INIT chunk length in COOKIE_ECHO processing When a listening SCTP server processes a COOKIE_ECHO chunk, the cached peer INIT chunk embedded after the cookie is parsed and its parameters are later walked by sctp_process_init() using sctp_walk_params(). However, the chunk header length of this cached INIT chunk was not validated against the remaining buffer in the COOKIE_ECHO payload. If the length field is inflated, the parameter walk can run beyond the actual received data, leading to out-of-bounds reads and potential memory corruption during later parameter handling (e.g. STATE_COOKIE processing and kmemdup() copies). Add a bounds check in sctp_unpack_cookie() to ensure the cached INIT chunk length does not exceed the available data in the COOKIE_ECHO buffer before it is used.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < cc272185c9a9a4b7febc2de52eeaa3d00f19091e (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < edccbf3d63b0a3362bc916ea72edacc1e1ca456a (git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 0861615c28de668669d748ef4eb913ea9262d13b (git)
guessed Create a notification for this product.
Linux Linux Affected: 2.6.12
Unaffected: 0 , < 2.6.12 (semver)
Unaffected: 6.18.36 , ≤ 6.18.* (semver)
Unaffected: 7.0.13 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
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}



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  • 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.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
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