CVE-2026-34990: OpenPrinting cups · Improper Authentication
Affects OpenPrinting cupsSource CVE Database V5
Not known to be exploited · CVSS 5.0 Medium.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 21% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:H/SI:H/SA:LExploitation evidence
Disclosed: evidence found.
CVE published 3 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: evidence found.
Public exploit code: GitHub proofs of concept
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), GitHub proofs of concept, the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| OpenPrintingcups | Affected
| Fixed in– |
GitHubopenprinting/cupspkg:github/openprinting/cupsOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
At the time of this report, no official patches or fixes are available for this vulnerability. Users should monitor the OpenPrinting project for updates and advisories. Until a fix is released, restricting local user access and limiting exposure to untrusted local users may reduce risk.
Description
CVE-2026-34990 is an improper authentication vulnerability in OpenPrinting CUPS versions 2.4.16 and earlier. A local unprivileged user can trick the CUPS daemon into authenticating to a malicious localhost IPP service using a reusable authorization token. This token allows the attacker to perform administrative requests locally, including creating a printer queue with a file URI that bypasses normal policy restrictions. Exploiting this flaw can lead to arbitrary root file overwrites, enabling privilege escalation to root. No patches or official fixes are available at the time of publication.