PaperCut NG/MF is widely deployed; vulnerability allows arbitrary code execution and is listed in CISA's KEV—high likelihood of org‑wide impact and newsworthiness.
CVE-2026-82078
Unsafe reflection in PaperCut NG/MF allows arbitrary Java bytecode execution.
Is CVE-2026-82078 being exploited?
Yes. CVE-2026-82078 appears in CISA's Known Exploited Vulnerabilities catalog, which means exploitation in the wild has been confirmed and reported. Treat it as active rather than theoretical, and patch it ahead of higher-scoring vulnerabilities that carry no exploitation evidence.
How severe is CVE-2026-82078?
CVE-2026-82078 is rated Critical with a CVSS score of 9.4. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-82078?
Yes. A fix has been recorded for CVE-2026-82078. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-82078 affect?
CVE-2026-82078 affects PaperCut NG, PaperCut MF. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-82078?
Apply vendor patch/mitigations immediately and isolate internet‑exposed PaperCut servers.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Arbitrary Java bytecode execution as the PaperCut server user via configurable DB driver names, enabling server compromise and lateral movement.
Immediate action required
- affected< 24.1.10, 25.0.13, 26.0.5
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.