{"id":"CVE-2026-115506","summary":"libexpat through 2.9.0 Denial of Service via Billion Laughs Detection Delay","details":"libexpat through 2.9.0 contains a denial of service vulnerability because billion laughs protection in accountingDiffTolerated() in xmlparse.c detects entity amplification too late. Attackers can supply a moderately sized XML document with a large DTD and nested entity expansions to consume tens of seconds of CPU per parse.","modified":"2026-11-04T17:27:19.179854893Z","published":"2026-10-22T19:14:06.001Z","related":["openSUSE-SU-2026:12396-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/115xxx/CVE-2026-115506.json","cna_assigner":"VulnCheck","cwe_ids":["CWE-776"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/115xxx/CVE-2026-115506.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-115506"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/libexpat-through-2.9.0-denial-of-service-via-billion-laughs-detection-delay"},{"type":"REPORT","url":"https://github.com/libexpat/libexpat/issues/1160"},{"type":"FIX","url":"https://github.com/libexpat/libexpat/pull/1433"},{"type":"PACKAGE","url":"https://github.com/libexpat/libexpat"},{"type":"EVIDENCE","url":"https://github.com/hannob/lololol"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/libexpat/libexpat","events":[{"introduced":"0"},{"last_affected":"a76b1174c1ea52abb639a4c69d52b630a8a106a2"}],"database_specific":{"extracted_events":[{"source":"AFFECTED_FIELD","strategy":"StandardRange","range":[{"introduced":"0"},{"last_affected":"2.9.0"}]},{"range":[{"introduced":"0"},{"last_affected":"2.9.0"}],"source":"CPE_RANGE","cpe":"cpe:2.3:a:libexpat_project:libexpat:*:*:*:*:*:*:*:*"}]}}],"versions":["R_2_9_0","R_2_8_5","R_2_8_4","R_2_8_3","R_2_8_2","R_2_8_1","R_2_8_0","R_2_7_5","R_2_7_4","R_2_7_3","R_2_7_2","R_2_7_1","R_2_7_0","R_2_6_4","R_2_6_3","R_2_6_2","R_2_6_1","R_2_6_0","R_2_5_0","R_2_4_9","R_2_4_8","R_2_4_7","R_2_4_6","R_2_4_5","R_2_4_4","R_2_4_3","R_2_4_2","R_2_4_1","R_2_4_0","R_2_3_0","R_2_2_10","R_2_2_9","R_2_2_8","R_2_2_7","R_2_2_6","R_2_2_5","R_2_2_4","R_2_2_3","R_2_2_2","R_2_2_1","R_2_2_0","R_2_1_1","R_2_1_0","R_2_0_1","R_2_0_0","R_1_95_8","R_1_95_7","R_1_95_6","R_1_95_5","R_1_95_4","R_1_95_3","R_1_95_2","R_1_95_0","libexpat-alpha-1","start","sourceforge_init","jclark-orig","V20000512","V19991013","V19990728","V19990709","V19990626","V1_1","V19990425","V1990307","V19990109","V19981231","V19981122","V1_0","beta4","beta3","beta2","REC1_0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-115506.json"}}],"schema_version":"1.9.2","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"}]}