OpenPrinting CUPS before 2.4.20 contains a double-free in printer-class management. When CUPS-Add-Modify-Class replaces an existing class member list, add_class() frees pclass->printers without clearing the pointer. If subsequent validation fails, the class retains the dangling pointer; CUPS-Delete-Class subsequently frees the same allocation in cupsdDeletePrinter(). A client authorized to modify and delete classes can cause scheduler-wide denial of service. The default policy requires @SYSTEM privileges.
Fix
Patch, vendor advisory and mitigation references on NVD 2
- https://github.com/OpenPrinting/cups/security/advisories/GHSA-pwg4-pv39-8c22 Exploit, Patch, Vendor Advisory
- https://github.com/OpenPrinting/cups/security/advisories/GHSA-pwg4-pv39-8c22 Exploit, Patch, Vendor Advisory
Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.
Change history 4
- Cpes+1 CPE criteria (now 1)NVD modified 2026-10-20 20:56
- StatusAwaiting Analysis → AnalyzedNVD modified 2026-10-20 20:56
- CVSS2.3 (v3.1, CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:L) → 6.5 (v3.1, CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H)NVD modified 2026-10-20 20:56
- First seenCVSS 2.3NVD modified 2026-10-09 18:17
Affected (CPE criteria) 1
cpe:2.3:a:openprinting:cups:*:*:*:*:*:*:*:*
References 2
- https://github.com/OpenPrinting/cups/security/advisories/GHSA-pwg4-pv39-8c22 Exploit, Patch, Vendor Advisory
- https://github.com/OpenPrinting/cups/security/advisories/GHSA-pwg4-pv39-8c22 Exploit, Patch, Vendor Advisory