Vulnerability Description
OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. In versions 2.4.16 and prior, the RSS notifier allows .. path traversal in notify-recipient-uri (e.g., rss:///../job.cache), letting a remote IPP client write RSS XML bytes outside CacheDir/rss (anywhere that is lp-writable). In particular, because CacheDir is group-writable by default (typically root:lp and mode 0770), the notifier (running as lp) can replace root-managed state files via temp-file + rename(). This PoC clobbers CacheDir/job.cache with RSS XML, and after restarting cupsd the scheduler fails to parse the job cache and previously queued jobs disappear. At time of publication, there are no publicly available patches.
CVSS Score
MEDIUM
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Openprinting | Cups | <= 2.4.16 |
Related Weaknesses (CWE)
References
- https://github.com/OpenPrinting/cups/security/advisories/GHSA-f53q-7mxp-9gcrExploitVendor Advisory
- https://github.com/OpenPrinting/cups/security/advisories/GHSA-f53q-7mxp-9gcrExploitVendor Advisory
FAQ
What is CVE-2026-34978?
CVE-2026-34978 is a vulnerability with a CVSS score of 6.5 (MEDIUM). OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. In versions 2.4.16 and prior, the RSS notifier allows .. path traversal in notify-recipient-uri (e....
How severe is CVE-2026-34978?
CVE-2026-34978 has been rated MEDIUM with a CVSS base score of 6.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-34978?
Check the references section above for vendor advisories and patch information. Affected products include: Openprinting Cups.