CVE-2026-34990

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.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/OpenPrinting/cups/security/advisories/GHSA-c54j-2vqw-wpwp	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:openprinting:cups:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-03 22:16

Updated : 2026-07-24 21:10

NVD link : CVE-2026-34990

Mitre link : CVE-2026-34990

CVE.ORG link : CVE-2026-34990

JSON object : View

Products Affected

openprinting

cups

CWE

CWE-287

Improper Authentication

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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."}, {"lang": "es", "value": "OpenPrinting CUPS es un sistema de impresi\u00f3n de c\u00f3digo abierto para Linux y otros sistemas operativos tipo Unix. En las versiones 2.4.16 y anteriores, un usuario local sin privilegios puede forzar a cupsd a autenticarse en un servicio IPP de localhost controlado por el atacante con un token de Autorizaci\u00f3n: Local ... reutilizable. Ese token es suficiente para impulsar solicitudes /admin/ en localhost, y el atacante puede combinar CUPS-Create-Local-Printer con printer-is-shared=true para persistir una cola file:///... aunque la pol\u00edtica normal de FileDevice rechaza tales URIs. Imprimir en esa cola permite una sobrescritura arbitraria de archivos de root; el PoC a continuaci\u00f3n utiliza esa primitiva para soltar un fragmento de sudoers y demostrar la ejecuci\u00f3n de comandos como root. En el momento de la publicaci\u00f3n, no hay parches disponibles p\u00fablicamente."}], "lastModified": "2026-07-24T21:10:00.143", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:openprinting:cups:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "8A2A4507-B2D7-43B8-B008-6EC2F5053FA9", "versionEndIncluding": "2.4.16"}], "operator": "OR"}]}], "sourceIdentifier": "security-advisories@github.com"}