sctp: validate cookie AUTH state before use
CVE-2026-74752 · published 26 Aug 2026
How serious is it
- Severity: critical, CVSS score 9.8 out of 10.
- No exploit prediction (EPSS) score yet.
- Not on the CISA list of exploited vulnerabilities.
- No public exploit in Exploit-DB.
Is your app affected by CVE-2026-74752?
Paste this prompt into Claude Code, Cursor or any AI coding tool: it runs a free Shippable scan of your project and fixes what it finds. Built with Lovable, Bolt or v0? Scan your live app. Or upload your package file.
Who is affected
- Linux Linux: 1f485649f52929d9937b346a920a522a7363e202 to < 4a4410de8dc6903d859c9e1731fc6dcee28bd072, 1f485649f52929d9937b346a920a522a7363e202 to < 7f17984cfa697613800eb693e183b06884129bd3, 1f485649f52929d9937b346a920a522a7363e202 to < 88619b117be1daf633ce32210570ce35a0bd1c98, 1f485649f52929d9937b346a920a522a7363e202 to < 3dbb44d88b1e94dd31fe43588af7437b34b44d56
- Linux Linux: 2.6.24
How to check
- Find out whether you run the affected product and which version, then compare it with the versions above.
How to fix
Copies a prompt for Claude Code, Cursor or Codex that asks it to check whether you run this product.
- Apply the vendor's update or mitigation from the references below. If there is none yet, limit exposure of the affected service until there is.
- If a vulnerable version was live, check your logs and rotate the secrets that server could read.
The advisory
In the Linux kernel, the following vulnerability has been resolved:
sctp: validate cookie AUTH state before use
When cookie authentication is disabled, COOKIE_ECHO restores fixed-size
AUTH fields directly from peer-controlled cookie bytes. A forged RANDOM
length, HMAC list, or CHUNKS list can then reach association consumers
with lengths or identifiers that were never validated against the local
backing arrays.
A forged RANDOM length can cause out-of-bounds reads during key-vector
construction. A forged HMAC identifier also caused a 32-byte write past
a zero-length AUTH chunk, providing a primitive for a local privilege
escalation chain.
Validate the cookie's RANDOM, HMACS, and CHUNKS parameters at the cookie
trust boundary before copying them into the association. Reject invalid
types, malformed lengths, unsupported HMAC identifiers, HMAC lists
without SHA1, and forbidden chunk ids.
Check your whole app
Dependencies are only half of it. Free and read-only: before you push, run npx shippable-dev scan localhost:3000 in your project folder, no account needed. For your live app, you prove it's yours with a one-line tag first.
References
- git.kernel.org/stable/c/4a4410de8dc6903d859c9e1731fc6dcee28bd072
- git.kernel.org/stable/c/7f17984cfa697613800eb693e183b06884129bd3
- git.kernel.org/stable/c/88619b117be1daf633ce32210570ce35a0bd1c98
- git.kernel.org/stable/c/3dbb44d88b1e94dd31fe43588af7437b34b44d56
Merged from CVE List. Last updated 25 Oct 2026. All vulnerabilities · RSS · JSON