CVE-2026-8794: PaperCut NG/MF · Timing Side Channel
Affects PaperCut NG/MFSource CVE Database V5
Not known to be exploited · CVSS 6.9 Medium : upgrade to 26.0.3 when convenient.
Data as of 1 Nov 2026, 22:58 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 52% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 26.0.3
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 3 Aug 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 1 Nov 2026.
What to do
Upgrade PaperCut NG/MF to 26.0.3.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| PaperCutPaperCut NG/MF | Affected
| Fixed in
|
AI-suggested
If you cannot patch yet, consider implementing additional monitoring or rate limiting on authentication attempts to reduce the risk of username enumeration.
Description
CVE-2026-8794 is a timing discrepancy vulnerability in the authentication component of PaperCut NG/MF. An unauthenticated remote attacker can exploit this issue to enumerate valid usernames by measuring response times during login attempts. The vulnerability arises because the system only performs a password hash comparison when a valid account is supplied, creating a timing oracle. This flaw can reveal account existence without authentication.