CISA Warns of Multiple PaperCut NG/MF Vulnerabilities Actively Exploited in Attacks

CISA added two critical PaperCut NG/MF vulnerabilities (CVE-2026-81578: missing authentication, and CVE-2026-82078: unsafe reflection) to its Known Exploited Vulnerabilities catalog after evidence of exploitation. The flaws can be chained to allow unauthenticated modification of server configuration and execution of arbitrary Java bytecode in the PaperCut server context, risking remote compromise of internet-exposed deployments; CISA set a remediation deadline for federal agencies and recommends immediate mitigation, access restriction, and forensic review where exposure occurred.