{"id":"CVE-2026-43970","aliases":["EEF-CVE-2026-43970","GHSA-84f2-rp86-235p"],"url":"https://o3.security/vulnerability/CVE-2026-43970","summary":"Decompression Bomb in cow_spdy:inflate/2 Allows Memory Exhaustion via Crafted SPDY Frame","details":"Improper Handling of Highly Compressed Data (Data Amplification) vulnerability in ninenines cowlib allows unauthenticated remote denial of service via memory exhaustion.\n\ncow_spdy:inflate/2 in cowlib passes peer-supplied compressed bytes directly to zlib:inflate/2 with no output size bound. The SPDY header compression dictionary (?ZDICT) is public, and zlib compresses long runs of repeated bytes at roughly 1024:1, so a few kilobytes of SPDY frame payload can decompress to gigabytes on the BEAM heap, OOM-killing the node. A single unauthenticated SPDY frame is sufficient to trigger the condition. The parsers for syn_stream, syn_reply, and headers frame types are all affected via cow_spdy:parse_headers/2.\n\nThis issue affects cowlib from 0.1.0 before 2.16.1.","published":"2026-05-13T18:43:11.640Z","modified":"2026-08-07T11:49:53.827870370Z","cvss":null,"epss":{"score":0.00511,"percentile":0.40795,"asOf":"2026-08-09"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Hex","name":"cowlib","fixedVersion":"2.16.1"}],"fix":{"url":"https://github.com/ninenines/cowlib/commit/16aad3fb9f81f5cda4d1706ff0c54237c619c282","label":"ninenines/cowlib@16aad3f"},"references":[{"type":"WEB","url":"https://github.com"},{"type":"WEB","url":"https://osv.dev/vulnerability/EEF-CVE-2026-43970"},{"type":"WEB","url":"https://repo.hex.pm"},{"type":"ADVISORY","url":"https://cna.erlef.org/cves/CVE-2026-43970.html"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43970.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-43970"},{"type":"FIX","url":"https://github.com/ninenines/cowlib/commit/16aad3fb9f81f5cda4d1706ff0c54237c619c282"},{"type":"PACKAGE","url":"https://github.com/ninenines/cowlib"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-07T11:49:53.827870370Z"}}