{"url":"http://public2.vulnerablecode.io/api/vulnerabilities/74620?format=json","vulnerability_id":"VCID-74v9-tmds-gbh4","summary":"The OWASP core rule set (CRS) is a set of generic attack detection rules for use with compatible web application firewalls. Prior to versions 4.22.0 and 3.3.8, the current rule 922110 has a bug when processing multipart requests with multiple parts. When the first rule in a chain iterates over a collection (like `MULTIPART_PART_HEADERS`), the capture variables (`TX:0`, `TX:1`) get overwritten with each iteration. Only the last captured value is available to the chained rule, which means malicious charsets in earlier parts can be missed if a later part has a legitimate charset. Versions 4.22.0 and 3.3.8 patch the issue.","aliases":[{"alias":"CVE-2026-21876"}],"fixed_packages":[{"url":"http://public2.vulnerablecode.io/api/packages/95066?format=json","purl":"pkg:deb/debian/modsecurity-crs@3.3.0-1%2Bdeb11u1?distro=trixie","is_vulnerable":true,"affected_by_vulnerabilities":[{"vulnerability":"VCID-sxke-mrk8-fkgg"}],"resource_url":"http://public2.vulnerablecode.io/packages/pkg:deb/debian/modsecurity-crs@3.3.0-1%252Bdeb11u1%3Fdistro=trixie"},{"url":"http://public2.vulnerablecode.io/api/packages/95074?format=json","purl":"pkg:deb/debian/modsecurity-crs@3.3.4-1~deb11u2?distro=trixie","is_vulnerable":false,"affected_by_vulnerabilities":[],"resource_url":"http://public2.vulnerablecode.io/packages/pkg:deb/debian/modsecurity-crs@3.3.4-1~deb11u2%3Fdistro=trixie"},{"url":"http://public2.vulnerablecode.io/api/packages/95076?format=json","purl":"pkg:deb/debian/modsecurity-crs@3.3.4-1%2Bdeb12u1?distro=trixie","is_vulnerable":false,"affected_by_vulnerabilities":[],"resource_url":"http://public2.vulnerablecode.io/packages/pkg:deb/debian/modsecurity-crs@3.3.4-1%252Bdeb12u1%3Fdistro=trixie"},{"url":"http://public2.vulnerablecode.io/api/packages/95064?format=json","purl":"pkg:deb/debian/modsecurity-crs@3.3.4-1%2Bdeb12u3?distro=trixie","is_vulnerable":false,"affected_by_vulnerabilities":[],"resource_url":"http://public2.vulnerablecode.io/packages/pkg:deb/debian/modsecurity-crs@3.3.4-1%252Bdeb12u3%3Fdistro=trixie"},{"url":"http://public2.vulnerablecode.io/api/packages/95078?format=json","purl":"pkg:deb/debian/modsecurity-crs@3.3.7-1%2Bdeb13u1?distro=trixie","is_vulnerable":false,"affected_by_vulnerabilities":[],"resource_url":"http://public2.vulnerablecode.io/packages/pkg:deb/debian/modsecurity-crs@3.3.7-1%252Bdeb13u1%3Fdistro=trixie"},{"url":"http://public2.vulnerablecode.io/api/packages/95068?format=json","purl":"pkg:deb/debian/modsecurity-crs@3.3.7-1%2Bdeb13u2?distro=trixie","is_vulnerable":false,"affected_by_vulnerabilities":[],"resource_url":"http://public2.vulnerablecode.io/packages/pkg:deb/debian/modsecurity-crs@3.3.7-1%252Bdeb13u2%3Fdistro=trixie"},{"url":"http://public2.vulnerablecode.io/api/packages/95077?format=json","purl":"pkg:deb/debian/modsecurity-crs@3.3.8-1?distro=trixie","is_vulnerable":false,"affected_by_vulnerabilities":[],"resource_url":"http://public2.vulnerablecode.io/packages/pkg:deb/debian/modsecurity-crs@3.3.8-1%3Fdistro=trixie"},{"url":"http://public2.vulnerablecode.io/api/packages/95067?format=json","purl":"pkg:deb/debian/modsecurity-crs@3.3.9-1?distro=trixie","is_vulnerable":false,"affected_by_vulnerabilities":[],"resource_url":"http://public2.vulnerablecode.io/packages/pkg:deb/debian/modsecurity-crs@3.3.9-1%3Fdistro=trixie"}],"affected_packages":[],"references":[{"reference_url":"https://api.first.org/data/v1/epss?cve=CVE-2026-21876","reference_id":"","reference_type":"","scores":[{"value":"0.03371","scoring_system":"epss","scoring_elements":"0.87637","published_at":"2026-06-11T12:55:00Z"}],"url":"https://api.first.org/data/v1/epss?cve=CVE-2026-21876"},{"reference_url":"https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-21876","reference_id":"","reference_type":"","scores":[],"url":"https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-21876"},{"reference_url":"https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1125084","reference_id":"1125084","reference_type":"","scores":[],"url":"https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1125084"},{"reference_url":"https://github.com/coreruleset/coreruleset/commit/80d80473abf71bd49bf6d3c1ab221e3c74e4eb83","reference_id":"80d80473abf71bd49bf6d3c1ab221e3c74e4eb83","reference_type":"","scores":[{"value":"9.3","scoring_system":"cvssv3.1","scoring_elements":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N"},{"value":"Track","scoring_system":"ssvc","scoring_elements":"SSVCv2/E:N/A:Y/T:P/P:M/B:A/M:M/D:T/2026-01-08T14:52:48Z/"}],"url":"https://github.com/coreruleset/coreruleset/commit/80d80473abf71bd49bf6d3c1ab221e3c74e4eb83"},{"reference_url":"https://github.com/coreruleset/coreruleset/commit/9917985de09a6cf38b3261faf9105e909d67a7d6","reference_id":"9917985de09a6cf38b3261faf9105e909d67a7d6","reference_type":"","scores":[{"value":"9.3","scoring_system":"cvssv3.1","scoring_elements":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N"},{"value":"Track","scoring_system":"ssvc","scoring_elements":"SSVCv2/E:N/A:Y/T:P/P:M/B:A/M:M/D:T/2026-01-08T14:52:48Z/"}],"url":"https://github.com/coreruleset/coreruleset/commit/9917985de09a6cf38b3261faf9105e909d67a7d6"},{"reference_url":"https://gitlab.com/exploit-database/exploitdb/-/blob/main/exploits/multiple/webapps/52558.py","reference_id":"CVE-2026-21876","reference_type":"exploit","scores":[],"url":"https://gitlab.com/exploit-database/exploitdb/-/blob/main/exploits/multiple/webapps/52558.py"},{"reference_url":"https://github.com/coreruleset/coreruleset/security/advisories/GHSA-36fv-25j3-r2c5","reference_id":"GHSA-36fv-25j3-r2c5","reference_type":"","scores":[{"value":"9.3","scoring_system":"cvssv3.1","scoring_elements":"CVSS:3.1/AV:N/AC:L/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