PatchTheCVECVE-2026-23409: In the Linux kernel, the following vulnerability has been resolved: apparmor: fix differential encoding verif
CVE-2026-23409 is a medium-severity flaw (CVSS 5.5) affecting linux kernel. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
In the Linux kernel, the following vulnerability has been resolved: apparmor: fix differential encoding verification Differential encoding allows loops to be created if it is abused. To prevent this the unpack should verify that a diff-encode chain terminates. Unfortunately the differential encode verification had two bugs. 1. it conflated states that had gone through check and already been marked, with states that were currently being che
Why this priority
- On your watchlist
A fixed release or distro patch exists.
Risk facts
| CVSS score | 5.5 (Medium) |
| Attack vector | Local |
| Attack complexity | Low |
| Privileges needed | Low |
| User interaction | None |
| EPSS exploit chance | 0.2% (top 93%) |
| CISA exploited list | No |
| Weakness | CWE-835 |
| Published | 2026-04-01 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-23409?
linux kernel: upgrade to 5.10.253, 5.15.203, 6.1.169, 6.6.130, 6.12.77, 6.18.18, 6.19.8. Exact commands for each OS are on this page.
Is CVE-2026-23409 being exploited?
CVE-2026-23409 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-23409 affect?
CVE-2026-23409 affects linux kernel. Severity is medium (CVSS 5.5). In the Linux kernel, the following vulnerability has been resolved: apparmor: fix differential encoding verification Differential encoding allows loops to be created if it is abused. To prevent this the unpack should verify that a diff-en
How urgent is CVE-2026-23409?
Priority 26/100. On your watchlist
Software pages
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