{"schemaVersion":3,"id":"CVE-2026-27858","aliases":["UBUNTU-CVE-2026-27858","DEBIAN-CVE-2026-27858"],"status":"published","duplicateOf":null,"title":null,"description":"Attacker can send a specifically crafted message before authentication that causes managesieve to allocate large amount of memory.\n Attacker can force managesieve-login to be unavailable by repeatedly crashing the process. Protect access to managesieve protocol, or install fixed version. 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