{"id":"AZL-79877","summary":"CVE-2026-23943 affecting package erlang for versions less than 26.2.5.18-1","details":"Improper Handling of Highly Compressed Data (Compression Bomb) vulnerability in Erlang OTP ssh (ssh_transport modules) allows Denial of Service via Resource Depletion.\n\nThe SSH transport layer advertises legacy zlib compression by default and inflates attacker-controlled payloads pre-authentication without any size limit, enabling reliable memory exhaustion DoS.\n\nTwo compression algorithms are affected:\n\n* zlib: Activates immediately after key exchange, enabling unauthenticated attacks\n* zlib@openssh.com: Activates post-authentication, enabling authenticated attacks\n\nEach SSH packet can decompress ~255 MB from 256 KB of wire data (1029:1 amplification ratio). Multiple packets can rapidly exhaust available memory, causing OOM kills in memory-constrained environments.\n\nThis vulnerability is associated with program files lib/ssh/src/ssh_transport.erl and program routines ssh_transport:decompress/2, ssh_transport:handle_packet_part/4.\n\nThis issue affects OTP from OTP 17.0 before OTP 28.4.1, OTP 27.3.4.9 and OTP 26.2.5.18, corresponding to ssh from 3.0.1 before 5.5.1, 5.2.11.6 and 5.1.4.14.","modified":"2026-08-28T17:47:53.032213791Z","published":"2026-03-13T19:54:15Z","upstream":["CVE-2026-23943"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-23943"}],"affected":[{"package":{"name":"erlang","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/erlang"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.2.5.18-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-79877.json"}}],"schema_version":"1.9.0"}