CVE-2026-68376

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux1f485649f52929d9937b346a920a522a7363e202 < 0b4414e43e0861d67276031cc21401d7e87de3daaffected
LinuxLinux1f485649f52929d9937b346a920a522a7363e202 < d0a59ba58578e2b330fff80a44fe519f3ba7d8c7affected
LinuxLinux1f485649f52929d9937b346a920a522a7363e202 < a8d20ba0ab518c9ccbcde258f25fc1ee6e51d5dbaffected
LinuxLinux1f485649f52929d9937b346a920a522a7363e202 < 3aa40c3bccac2312ea7cf97f329190637f972b5daffected
LinuxLinux1f485649f52929d9937b346a920a522a7363e202 < e0b5252a59383b77d1b8dbeda00b7184dd95f4d3affected
LinuxLinux2.6.24affected
LinuxLinux0 < 2.6.24unaffected
LinuxLinux6.6.148 <= 6.6.*unaffected
LinuxLinux6.12.101 <= 6.12.*unaffected
LinuxLinux6.18.42 <= 6.18.*unaffected
LinuxLinux7.1.6 <= 7.1.*unaffected
LinuxLinux7.2-rc4 <= *unaffected

Weaknesses

References