CVE-2026-53080: Linux kernel · NULL Pointer Dereference
Source GCVE Database
Not known to be exploited · CVSS 5.5 Medium.
Data as of 26 Oct 2026, 17:16 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.
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 24 Jun 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
AI-suggested
Until a fix is applied, avoid using or loading cls_fw filters created with the old method on shared blocks. Monitor vendor communications for an official fix or temporary workaround. No specific mitigation is documented beyond avoiding the vulnerable usage pattern.
Description
A vulnerability in the Linux kernel's cls_fw module could cause a NULL pointer dereference due to improper handling of "old-style" filters before their change() function is called. This issue can lead to kernel warnings and potential denial of service. The problem arises because invalid filters created with the old method can classify packets before being destroyed, causing a NULL dereference in fw_classify().
References
- nvd.nist.gov/vuln/detail/CVE-2026-53080 (opens in a new tab)
- git.kernel.org/stable/c/41845bc5bb64f3d615abe575ad655b5e7f193634 (opens in a new tab)
- git.kernel.org/stable/c/4fabcfea7a9dd159df32c5df6587fe858cb0d748 (opens in a new tab)
- git.kernel.org/stable/c/5dcce34c57d5e5990869384d69deeb9414bf9b92 (opens in a new tab)
- git.kernel.org/stable/c/5df49f0579f7e625f2358a219d31fbc7621be799 (opens in a new tab)
- git.kernel.org/stable/c/65782b2db7321d5f97c16718c4c7f6c7205a56be (opens in a new tab)
- git.kernel.org/stable/c/829808cbf8cf8a6d07a0e67a5ea2c3fcd63a9e5c (opens in a new tab)
- git.kernel.org/stable/c/a719275da488835e987d28effc04679b4aace3a0 (opens in a new tab)
- git.kernel.org/stable/c/c205da704c84eeb4247d770150440294fd547049 (opens in a new tab)
- cert-portal.siemens.com/productcert/html/ssa-784472.html (opens in a new tab)