{"id":"CVE-2026-52761","summary":"ModSecurity: Transformation utf8toUnicode produces wrong output on i386 architecture","details":"ModSecurity is an open source, cross platform web application firewall (WAF) engine for Apache, IIS and Nginx. From 3.0.0 through 3.0.15, the t:utf8toUnicode transformation in src/actions/transformations/utf8_to_unicode.cc produces wrong output on i386 architecture because snprintf uses sizeof on a char pointer rather than the length of the unicode buffer, allowing rules that use this transformation to be bypassed on i386 architecture. This issue is fixed in version 3.0.16.","aliases":["BIT-modsecurity-2026-52761","BIT-modsecurity2-2026-52761","GHSA-qjgm-7gp4-f8qq"],"modified":"2026-08-27T08:32:57.451362Z","published":"2026-07-10T21:40:23.961Z","database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-467"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/52xxx/CVE-2026-52761.json"},"references":[{"type":"WEB","url":"https://github.com/owasp-modsecurity/ModSecurity/releases/tag/v3.0.16"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/52xxx/CVE-2026-52761.json"},{"type":"ADVISORY","url":"https://github.com/owasp-modsecurity/ModSecurity/security/advisories/GHSA-qjgm-7gp4-f8qq"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-52761"},{"type":"FIX","url":"https://github.com/owasp-modsecurity/ModSecurity/commit/edcd010814e234d46e2ec55a0f1078ff9d3032e4"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/owasp-modsecurity/modsecurity","events":[{"introduced":"c1cd668acb820824e791ba802396c60900eae9c1"},{"fixed":"edcd010814e234d46e2ec55a0f1078ff9d3032e4"},{"fixed":"7ea9fefbe0ba409d8733b4d682c8c4c059cd028d"}],"database_specific":{"cpe":"cpe:2.3:a:owasp:modsecurity:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"3.0.0"},{"last_affected":"3.0.15"}],"source":["CPE_RANGE","REFERENCES"]}}],"versions":["v4.0.0.0","v3.0.15","v3.0.14","v3.0.13","v3.0.12","v3.0.11","v3.0.10","v3.0.9","v3.0.8","v3.0.7","v3.0.6","v3.0.5","v3.0.4","v3.0.3","v3.0.2","v3.0.1","v3.0.0"],"database_specific":{"vanir_signatures":[{"deprecated":false,"digest":{"function_hash":"189875566307153264759742478548873607075","length":4162},"id":"CVE-2026-52761-7232b911","signature_type":"Function","signature_version":"v1","source":"https://github.com/owasp-modsecurity/modsecurity/commit/edcd010814e234d46e2ec55a0f1078ff9d3032e4","target":{"file":"src/actions/transformations/utf8_to_unicode.cc","function":"encode"}},{"deprecated":false,"digest":{"line_hashes":["79772351643922581001507942940615553275","51855614802641850113864520576721124036","43520524375649707598218463086627481483","185266507617586194539802336342961095591","124748630253991070031061963493082400457","5676183380359607255463324303236985202","123308590795090313962207814274805285879","199871826032601946481378403029451680933","17827673864226728656433031948682731291","62938945345873348389668743653887994473","131844961014464671930303173297281415561","42347015930452766397221733516769176545","59084688124245588210218372618972504722","189636792272493590742475699903134565297","232929058185679866918954565425526792281","39254513050279714723525506804828863675","5676183380359607255463324303236985202","123308590795090313962207814274805285879","199871826032601946481378403029451680933","17827673864226728656433031948682731291","62938945345873348389668743653887994473","131844961014464671930303173297281415561","42347015930452766397221733516769176545","59084688124245588210218372618972504722","189636792272493590742475699903134565297","232929058185679866918954565425526792281","67512179264863464612112034315869493803","5676183380359607255463324303236985202","123308590795090313962207814274805285879","199871826032601946481378403029451680933","17827673864226728656433031948682731291","62938945345873348389668743653887994473","131844961014464671930303173297281415561","42347015930452766397221733516769176545","59084688124245588210218372618972504722","189636792272493590742475699903134565297","232929058185679866918954565425526792281"],"threshold":0.9},"id":"CVE-2026-52761-da3fc2e4","signature_type":"Line","signature_version":"v1","source":"https://github.com/owasp-modsecurity/modsecurity/commit/edcd010814e234d46e2ec55a0f1078ff9d3032e4","target":{"file":"src/actions/transformations/utf8_to_unicode.cc"}}],"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-52761.json","vanir_signatures_modified":"2026-08-27T08:32:57Z"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N"}]}