{"id":"DEBIAN-CVE-2026-55204","details":"HAProxy through  3.4.0, fixed in commit 9a6d1fe, contains a null pointer dereference vulnerability in hpack_dht_insert() within src/hpack-tbl.c that fails to validate the return value of hpack_dht_defrag() when the memory pool is exhausted. An attacker can trigger HPACK dynamic table insertions under memory pressure to dereference a NULL pointer and crash HAProxy worker processes, causing denial of service.","modified":"2026-09-01T16:04:37.149496792Z","published":"2026-06-18T17:16:34.567Z","upstream":["CVE-2026-55204"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2026-55204"}],"affected":[{"package":{"name":"haproxy","ecosystem":"Debian:12","purl":"pkg:deb/debian/haproxy?arch=source&distro=bookworm"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.6.12-1","2.6.12-1+deb12u1","2.6.12-1+deb12u2","2.6.12-1+deb12u3","2.6.13-1","2.6.14-1","2.6.15-1","2.7.0-1","2.7.1-1","2.7.2-1","2.7.2-2","2.7.3-1","2.7.4-1","2.7.5-1","2.7.6-1","2.7.7-1","2.7.8-1","2.8.0-1","2.8.1-1","2.8.2-1","2.8.3-1","2.8.4-1","2.8.4-2","2.8.5-1","2.9.0-1","2.9.1-1","2.9.10-1","2.9.11-1","2.9.12-1","2.9.2-1","2.9.3-1","2.9.4-1","2.9.5-1","2.9.6-1","2.9.7-1","2.9.8-1","2.9.9-1","3.0.0-1","3.0.1-1","3.0.10-1","3.0.11-1","3.0.2-1","3.0.3-1","3.0.4-1","3.0.5-1","3.0.6-1","3.0.6-2","3.0.6-3","3.0.7-1","3.0.8-1","3.0.9-1","3.1.0-1","3.1.0-2","3.1.1-1","3.1.2-1","3.1.3-1","3.1.5-1","3.1.6-1","3.1.7-1","3.2.0-1","3.2.1-1","3.2.10-1","3.2.11-1","3.2.11-2","3.2.12-1","3.2.13-1","3.2.14-1","3.2.15-1","3.2.16-1","3.2.17-1","3.2.18-1","3.2.19-1","3.2.20-1","3.2.21-1","3.2.22-1","3.2.23-1","3.2.3-1","3.2.3-2","3.2.4-1","3.2.5-1","3.2.5-2","3.2.6-1","3.2.7-1","3.2.8-1","3.2.9-1","3.3.0-1","3.3.1-1","3.3.10-1","3.3.2-1","3.3.2-2","3.3.3-1","3.3.4-1","3.3.5-1","3.3.6-1","3.3.7-1","3.3.8-1","3.3.9-1","3.4.0-1","3.4.1-1","3.4.2-1","3.4.3-1","3.4.4-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-55204.json"}},{"package":{"name":"haproxy","ecosystem":"Debian:13","purl":"pkg:deb/debian/haproxy?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.0.11-1","3.0.11-1+deb13u1","3.0.11-1+deb13u2","3.0.11-1+deb13u3","3.1.0-1","3.1.0-2","3.1.1-1","3.1.2-1","3.1.3-1","3.1.5-1","3.1.6-1","3.1.7-1","3.2.0-1","3.2.1-1","3.2.10-1","3.2.11-1","3.2.11-2","3.2.12-1","3.2.13-1","3.2.14-1","3.2.15-1","3.2.16-1","3.2.17-1","3.2.18-1","3.2.19-1","3.2.20-1","3.2.21-1","3.2.22-1","3.2.23-1","3.2.3-1","3.2.3-2","3.2.4-1","3.2.5-1","3.2.5-2","3.2.6-1","3.2.7-1","3.2.8-1","3.2.9-1","3.3.0-1","3.3.1-1","3.3.10-1","3.3.2-1","3.3.2-2","3.3.3-1","3.3.4-1","3.3.5-1","3.3.6-1","3.3.7-1","3.3.8-1","3.3.9-1","3.4.0-1","3.4.1-1","3.4.2-1","3.4.3-1","3.4.4-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-55204.json"}},{"package":{"name":"haproxy","ecosystem":"Debian:14","purl":"pkg:deb/debian/haproxy?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.2.20-1"}]}],"versions":["3.0.11-1","3.1.0-1","3.1.0-2","3.1.1-1","3.1.2-1","3.1.3-1","3.1.5-1","3.1.6-1","3.1.7-1","3.2.0-1","3.2.1-1","3.2.10-1","3.2.11-1","3.2.11-2","3.2.12-1","3.2.13-1","3.2.14-1","3.2.15-1","3.2.16-1","3.2.17-1","3.2.18-1","3.2.19-1","3.2.3-1","3.2.3-2","3.2.4-1","3.2.5-1","3.2.5-2","3.2.6-1","3.2.7-1","3.2.8-1","3.2.9-1"],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-55204.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X"}]}