CVE-2026-31677: Linux kernel · crypto: af_alg – limit RX SG extraction by receive buffer budget
Source GCVE Database
Not known to be exploited · CVSS 5.5 Medium · fixed in 960c56743988d8ce9ff9b5d770dbeb5f64823a23 : update Linux kernel when convenient.
Data as of 30 Oct 2026, 16:33 UTC
Thin evidence
One scorer or none- Patch
- Available – fixed in 960c56743988d8ce9ff9b5d770dbeb5f64823a23, 9bf3e6ccfdcfe56ae3190d1ae987dacf1cfef4f9, 8eceab19eba9dcbfd2a0daec72e1bf48aa100170 +3
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 25 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 30 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: crypto: af_alg - limit RX SG extraction by receive buffer budget Make af_alg_get_rsgl() limit each RX scatterlist extraction to the remaining receive buffer budget. af_alg_get_rsgl() currently uses af_alg_readable() only as a gate before extracting data into the RX scatterlist. Limit each extraction to the remaining af_alg_rcvbuf(sk) budget so that receive-side accounting matches the amount of data attached to the request. If skcipher cannot obtain enough RX space for at least one chunk while more data remains to be processed, reject the recvmsg call instead of rounding the request length down to zero.
References
- nvd.nist.gov/vuln/detail/CVE-2026-31677 (opens in a new tab)
- git.kernel.org/stable/c/07c6f6ffe29009426f0bd4d3cfbb6308b8ea8453 (opens in a new tab)
- git.kernel.org/stable/c/4a264b2614c73c96666e196bbabe0cead52bdba7 (opens in a new tab)
- git.kernel.org/stable/c/7e345de2e69475430af85e09210795d8eb8e719c (opens in a new tab)
- git.kernel.org/stable/c/8eceab19eba9dcbfd2a0daec72e1bf48aa100170 (opens in a new tab)
- git.kernel.org/stable/c/960c56743988d8ce9ff9b5d770dbeb5f64823a23 (opens in a new tab)
- git.kernel.org/stable/c/9bf3e6ccfdcfe56ae3190d1ae987dacf1cfef4f9 (opens in a new tab)