{"id":"CVE-2026-6409","aliases":["GHSA-p2gh-cfq4-4wjc"],"url":"https://o3.security/vulnerability/CVE-2026-6409","summary":"Denial of Service (DoS) vulnerability exists in the Protobuf PHP library during the parsing of untrusted input","details":"### Impact\nA Denial of Service (DoS) vulnerability exists in the Protobuf PHP library during the parsing of untrusted input. Maliciously structured messages—specifically those containing negative `varint`s or deep recursion—can be used to crash the application, impacting service availability.\n\n### Patches\nPatches have been released to 5.34.0-RC1 and 4.33.6.","published":"2026-04-16T14:30:51.568Z","modified":"2026-08-12T16:09:58.193765Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Packagist","name":"google/protobuf","fixedVersion":"4.33.6"}],"fix":{"url":"https://github.com/protocolbuffers/protobuf/commit/60e93d2d104f2af9cd345b1c6f3891d91430244a","label":"protocolbuffers/protobuf@60e93d2"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/6xxx/CVE-2026-6409.json"},{"type":"ADVISORY","url":"https://github.com/protocolbuffers/protobuf/security/advisories/GHSA-p2gh-cfq4-4wjc"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-6409"},{"type":"WEB","url":"https://github.com/protocolbuffers/protobuf/issues/24159"},{"type":"WEB","url":"https://github.com/protocolbuffers/protobuf/issues/25067"},{"type":"WEB","url":"https://github.com/protocolbuffers/protobuf/commit/60e93d2d104f2af9cd345b1c6f3891d91430244a"},{"type":"WEB","url":"https://github.com/protocolbuffers/protobuf/commit/c8e9b27d95c6ab2d0668b5889e7dac2c477b7038"},{"type":"PACKAGE","url":"https://github.com/protocolbuffers/protobuf"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T16:09:58.193765Z"}}