{"id":"DEBIAN-CVE-2026-7790","details":"Uncontrolled Resource Consumption vulnerability in ninenines cowlib (cow_http_te module) allows Excessive Allocation.  The chunked transfer-encoding parser in cow_http_te accepts an unbounded number of hex digits in the chunk-size field. Each digit causes a bignum multiplication (Len * 16 + digit), so parsing N hex digits requires O(N²) CPU work and O(N) memory. Additionally, when input is drip-fed, the parser discards the accumulated length on each partial read and restarts from zero on resumption, raising the cost to O(N³). An unauthenticated remote attacker can exploit this by sending an HTTP/1.1 request with Transfer-Encoding: chunked and a very long chunk-size hex string to cause denial of service through CPU exhaustion and memory amplification.  This vulnerability is associated with program file src/cow_http_te.erl and program routines cow_http_te:stream_chunked/2, cow_http_te:chunked_len/4.  This issue affects cowlib: from 0.6.0 before 2.16.1.","modified":"2026-09-14T17:03:34.048660754Z","published":"2026-05-11T19:16:29.477Z","upstream":["CVE-2026-7790"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-7790"}],"affected":[{"package":{"name":"erlang-cowlib","ecosystem":"Debian:12","purl":"pkg:deb/debian/erlang-cowlib?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.3.0-3","2.17.1-1","2.17.1-2","2.18.0-1","2.19.0-1","2.20.0-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-7790.json"}},{"package":{"name":"erlang-cowlib","ecosystem":"Debian:13","purl":"pkg:deb/debian/erlang-cowlib?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.3.0-3","2.17.1-1","2.17.1-2","2.18.0-1","2.19.0-1","2.20.0-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-7790.json"}},{"package":{"name":"erlang-cowlib","ecosystem":"Debian:14","purl":"pkg:deb/debian/erlang-cowlib?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.17.1-1"}]}],"versions":["1.3.0-3"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-7790.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}