CVE-2026-74564: Linux kernel · netfilter: xt_hashlimit: validate hashtable supports XT_HASHLIMIT_RATE_MATCH
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 7.1 High · fixed in 5.15.0-1117.124~20.04.1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 14:05 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 1% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.15.0-1117.124~20.04.1, 5.15.0-1123.132~20.04.1, 5.15.0-1122.131~20.04.1 +28
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 15 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 |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: xt_hashlimit: validate hashtable supports XT_HASHLIMIT_RATE_MATCH The XT_HASHLIMIT_RATE_MATCH flag mode changes the semantics of the dsthash_ent structure which represents an entry in the hashtable. There is a union area which uses a different layout to express the rate match mode. Update .checkentry path to validate the XT_HASHLIMIT_RATE_MATCH mode flag is requested by two or more different rules that refer to the same hashtable. Otherwise, uninitialized access to the burst field in the union is possible. Reject the use of the XT_HASHLIMIT_RATE_MATCH mode flag if set on by revision less than 3 too.
References
- ubuntu.com/security/CVE-2026-74564 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-74564 (opens in a new tab)
- git.kernel.org/linus/305b63e1402267459fdabb183af4527f6799eebf (opens in a new tab)
- git.kernel.org/stable/c/06a76334243ccd875a981aa8bb46c0f931ef1e3b (opens in a new tab)
- git.kernel.org/stable/c/24683fea1f06bd3bd2707b99460e859bc6464c22 (opens in a new tab)
- git.kernel.org/stable/c/305b63e1402267459fdabb183af4527f6799eebf (opens in a new tab)
- git.kernel.org/stable/c/32ec8d4aba2cf22e12bdc28df8c4bd833c195fc0 (opens in a new tab)
- git.kernel.org/stable/c/d186f77d18bdfb252d401ff992ca3001a6a65a0f (opens in a new tab)
- ubuntu.com/security/notices/USN-8876-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8878-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8879-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8877-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8875-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8886-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8875-2 (opens in a new tab)