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CISA Adds Two Known Exploited Vulnerabilities to Catalog

highExploit / PoC exploited in the wildimportance 76CVE-2026-81578CVE-2026-82078
AI summary · glm-5.3-flash

CISA added actively exploited PaperCut NG/MF flaws CVE-2026-81578 and CVE-2026-82078 to the KEV catalog, mandating federal patching.

CISA added two vulnerabilities to its Known Exploited Vulnerabilities catalog based on evidence of active exploitation: CVE-2026-81578 (PaperCut NG/MF missing authentication for critical function) and CVE-2026-82078 (PaperCut NG/MF unsafe reflection). Under Binding Operational Directive 26-04, Federal Civilian Executive Branch agencies are required to prioritize and apply these updates. The KEV listing signals observed exploitation of the PaperCut print management platform.

  • Two PaperCut NG/MF vulnerabilities added to the KEV catalog.
  • CVE-2026-81578 is missing authentication; CVE-2026-82078 is unsafe reflection.
  • BOD 26-04 requires FCEB agencies to patch within required timeframes.
OrganizationsCISA
CountriesUnited States

Vulnerabilities mentionedAll →

CVEVulnerabilityCVSSEPSSFlagsAffectedExposurePublished
CVE-2026-82078
+1 in the same advisory: …81578
Unsafe Reflection RCE in PaperCut NG/MF, Chained with Auth Bypass in Attacks

CVE-2026-82078 is an unsafe dynamic class loading flaw (unsafe reflection, CWE-470) in the database connection utilities of PaperCut NG and PaperCut MF: the software instantiates a database driver class based on a configurable driver name without validating it against an allowlist of approved drivers. An attacker who can manipulate system configuration parameters can point that setting at classes of their choosing, causing the server to execute arbitrary Java bytecode residing on the application classpath in the security context of the PaperCut server process. On its own the issue is rated 9.4 (Critical) with high privileges required, but when chained with the companion authentication bypass CVE-2026-81578 it yields unauthenticated remote code execution on the print-management server. All PaperCut NG and MF deployments are in scope; affected version ranges were not specified in the available data, so administrators should consult PaperCut's advisory for fixed versions. The flaw is confirmed exploited in the wild as a zero-day: it was added to CISA's KEV catalog on 2026-08-31, and public reporting describes an AI-orchestrated campaign that compromised PaperCut servers at roughly 395 organizations (~440 servers), with EPSS currently at 1.7% (76th percentile).

Do: Upgrade PaperCut NG and MF to the patched release specified in PaperCut's security advisory (exact fixed versions were not provided in this data), prioritizing internet-exposed print servers; the KEV listing means agencies must remediate per CISA BOD 26-04 or discontinue/mitigate per its cloud-service guidance. Restrict the PaperCut web interface from direct internet exposure (VPN/allowlist), review administrator accounts and database driver configuration for tampering, and hunt for post-exploitation activity, since this flaw is being actively chained with the authentication bypass CVE-2026-81578.

9.4
group max
2% KEV
  • PaperCut NG
  • PaperCut MF
mass≈100,000+ organizations / plausibly millions of end users (vendor-cited install base); tens of thousands of on-prem servers with a smaller but significant…
Full article

CISA has added two new vulnerabilities to its Known Exploited Vulnerabilities (KEV) Catalog, based on evidence of active exploitation. CVE-2026-81578 PaperCut NG/MF Missing Authentication for Critical Function Vulnerability CVE-2026-82078 PaperCut NG/MF Unsafe Reflection Vulnerability These types of vulnerabilities are a frequent attack vector for malicious cyber actors and pose significant risks to the federal enterprise. Binding Operational Directive (BOD) 26-04: Prioritizing Security Updates Based on Risk establishes vulnerability management requirements for Federal Civilian Executive Branch (FCEB) agencies. BOD 26-04 reinforces the importance of the KEV Catalog and requires federal…

This source does not provide full text. Read it at cisa.gov.