Vulnerability · Published Apr 3, 2026 · Assigned by GitHub_M
CVE-2026-34990OpenPrinting CUPS: Local print admin token disclosure using temporary printers
High 7.8
In plain English
A high-severity improper authentication in cups from OpenPrinting. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 22% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.
Official description
OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. In versions 2.4.16 and prior, a local unprivileged user can coerce cupsd into authenticating to an attacker-controlled localhost IPP service with a reusable Authorization: Local ... token. That token is enough to drive /admin/ requests on localhost, and the attacker can combine CUPS-Create-Local-Printer with printer-is-shared=true to persist a file:///... queue even though the normal FileDevice policy rejects such URIs. Printing to that queue gives an arbitrary root file overwrite; the PoC below uses that primitive to drop a sudoers fragment and demonstrate root command execution. At time of publication, there are no publicly available patches.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.20 | cups | 2.4.18-r0 | ALPINE-CVE-2026-34990 |
| Alpine:v3.21 | cups | 2.4.18-r0 | ALPINE-CVE-2026-34990 |
| Alpine:v3.22 | cups | 2.4.18-r0 | ALPINE-CVE-2026-34990 |
| Alpine:v3.23 | cups | 2.4.18-r0 | ALPINE-CVE-2026-34990 |
| Alpine:v3.24 | cups | 2.4.18-r0 | ALPINE-CVE-2026-34990 |
| Debian:12 | cups | no fix listed | DEBIAN-CVE-2026-34990 |
| Debian:13 | cups | no fix listed | DEBIAN-CVE-2026-34990 |
| Debian:14 | cups | 2.4.17-1 | DEBIAN-CVE-2026-34990 |
| Ubuntu:22.04:LTS | cups | 2.4.1op1-1ubuntu4.20 | USN-8405-1 |
| Ubuntu:22.04:LTS | cups | 2.4.1op1-1ubuntu4.20 | UBUNTU-CVE-2026-34990 |
| Ubuntu:24.04:LTS | cups | 2.4.7-1.2ubuntu7.13 | USN-8405-1 |
| Ubuntu:24.04:LTS | cups | 2.4.7-1.2ubuntu7.13 | UBUNTU-CVE-2026-34990 |
| Ubuntu:25.10 | cups | 2.4.12-0ubuntu3.9 | USN-8405-1 |
| Ubuntu:25.10 | cups | 2.4.12-0ubuntu3.9 | UBUNTU-CVE-2026-34990 |
| Ubuntu:26.04:LTS | cups | 2.4.16-1ubuntu1.2 | UBUNTU-CVE-2026-34990 |
| Ubuntu:26.04:LTS | cups | 2.4.16-1ubuntu1.2 | USN-8405-1 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| OpenPrinting | cups | <= 2.4.16 |
Weakness: CWE-287 · Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
References
- https://github.com/OpenPrinting/cups/security/advisories/GHSA-c54j-2vqw-wpwp x_refsource_CONFIRM