CVE-2026-55222

5.1 MEDIUM 0.1% exploit odds Fix listed Other OS & kernel

What it is

Isar is an integration system for automated root filesystem generation. In versions 0.11 and newer, /etc/apt/trusted.gpg.d is created manually during bootstrap setup to be able to deploy local keys. By that, the directory is owned by the calling user (the one that executes Isar) instead of root. If the calling user's id is identical to one of an unprivileged user inside the image, this user is able to alter existing keys and deploy new ones, silently breaking the apt repo integrity protection. The issue is has no impact on those images that use an immutable rootfs, or if apt is never invoked. Changing only the keys does not trigger an exploit, it's just one step in a chain. An attacker would also have to manipulate a remote repo or intercept non-secure communication with it. This issue has been patched via commit 29e84ed.

At a glance

Exploitability: Can be exploited locally on the machine without logging in. High risk of data tampering.
Exploit odds: 0.1% chance of exploitation in the next 30 days (EPSS).
Fix: A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

2026-10-23 15:17 UTC PublishedDisclosed publicly on CVE.org and NVD
2026-10-23 21:17 UTC Last updatedMost recent change to the record

Why it ranks here

Exploited in the wild: no, CISA does not list it.
Exploit odds: 0.1% in the next 30 days (EPSS).
Severity: 5.1 MEDIUM (CVSS).
Fix: a patch or advisory is linked.

Details

Published: 2026-10-23 15:17 UTC
Last modified: 2026-10-23 21:17 UTC
Exploit probability: 0.1% · EPSS, next 30 days
Weakness: CWE-1290
Record status: Deferred

Attack profile CVSS 3.1 · 5.1

Attack vector: Local
Complexity: High
Privileges needed: None
User interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: High
Availability: None

Raw vector

CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2026-55222.md and follow it. Check whether this project is affected by CVE-2026-55222. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

· More options · Status badge

Download Square Reddit

Fix and advisories

References

NVD record · CVE.org record