{"id":"CVE-2026-55612","title":"uhttpd vulnerable to HTTP request smuggling via invalid chunk-length state reset","summary":"uhttpd is a small HTTP server. In unpatched repository snapshots, `client_poll_post_data()` in `client.c` consumes an invalid chunk-length line, such as a size exceeding INT_MAX, then clears `r->content_length` and `r->transfer_chunked` …","severity":"low","cvss":3.7,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","cvssSource":"cna","cwe":["CWE-444"],"vendor":"openwrt","product":"uhttpd","affected":["uhttpd >= b7c85a2819b3869279a669d5681f574824589c6c, < b78f518478794e16ba3568fc1258e40bf3e8eb3b","uhttpd >= b7c85a2819b3869279a669d5681f574824589c6c, < 34460b8211d676ef1b9f40d6b775c5e112933690"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-11-02T17:03:23.416603Z"},"published":"2026-10-30","updated":"2026-11-02","sourceUpdated":"2026-11-02T18:09:13.455Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-55612","references":[{"url":"https://github.com/openwrt/uhttpd/security/advisories/GHSA-p55c-rmhc-qfm5","label":"https://github.com/openwrt/uhttpd/security/advisories/GHSA-p55c-rmhc-qfm5"},{"url":"https://github.com/openwrt/uhttpd/commit/34460b8211d676ef1b9f40d6b775c5e112933690","label":"https://github.com/openwrt/uhttpd/commit/34460b8211d676ef1b9f40d6b775c5e112933690"},{"url":"https://github.com/openwrt/uhttpd/commit/b78f518478794e16ba3568fc1258e40bf3e8eb3b","label":"https://github.com/openwrt/uhttpd/commit/b78f518478794e16ba3568fc1258e40bf3e8eb3b"}],"tags":["cve.org"],"epss":0.0029,"epssPercentile":0.21648,"ingestedAt":"2026-11-05T19:30:42.766Z","slug":"CVE-2026-55612","body":"## Overview\n\nuhttpd is a small HTTP server. In unpatched repository snapshots, `client_poll_post_data()` in `client.c` consumes an invalid chunk-length line, such as a size exceeding INT_MAX, then clears `r->content_length` and `r->transfer_chunked` without draining the remaining body or setting `request.connection_close`. The completion check treats the chunked POST as finished and the keep-alive parser returns to `CLIENT_STATE_INIT`. Attacker-controlled body bytes aligned as a complete HTTP request are then parsed and processed as another request on the same connection, causing HTTP request smuggling and request-boundary desynchronization. Commits b78f518478794e16ba3568fc1258e40bf3e8eb3b and 34460b8211d676ef1b9f40d6b775c5e112933690 patch the issue.\n\n## Affected\n\n- `uhttpd >= b7c85a2819b3869279a669d5681f574824589c6c, < b78f518478794e16ba3568fc1258e40bf3e8eb3b`\n- `uhttpd >= b7c85a2819b3869279a669d5681f574824589c6c, < 34460b8211d676ef1b9f40d6b775c5e112933690`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":20,"depthScoreParts":{"impact":20.4,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}