{"id":"CVE-2026-55612","aliases":["EUVD-2026-114561","GHSA-p55c-rmhc-qfm5"],"status":"published","title":"uhttpd vulnerable to HTTP request smuggling via invalid chunk-length state reset","description":"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-\u003econtent_length` and `r-\u003etransfer_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.","severity":{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"low","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.0029,"percentile":0.21816,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-444"],"published":"2026-10-30T22:00:19Z","modified":"2026-11-04T02:30:20Z","products":[{"vendor":"openwrt","product":"uhttpd"}],"references":[{"url":"https://github.com/openwrt/uhttpd/security/advisories/GHSA-p55c-rmhc-qfm5","tags":["x_refsource_CONFIRM","advisory"]},{"url":"https://github.com/openwrt/uhttpd/commit/34460b8211d676ef1b9f40d6b775c5e112933690","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/openwrt/uhttpd/commit/b78f518478794e16ba3568fc1258e40bf3e8eb3b","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/55xxx/CVE-2026-55612.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-55612","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-55612","title":"uhttpd vulnerable to HTTP request smuggling via invalid chunk-length state reset","description":"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-\u003econtent_length` and `r-\u003etransfer_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.","status":"published","published":"2026-10-30T22:00:19.756Z","modified":"2026-11-02T18:09:13.455Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"low","assessor":"cna"}],"cwes":["CWE-444"],"updated_at":"2026-11-02T19:47:07.544208Z"}],"euvd":[{"id":"EUVD-2026-114561","description":"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-\u003econtent_length` and `r-\u003etransfer_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.","status":"published","published":"2026-10-30T22:00:19Z","modified":"2026-11-02T18:09:13Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"low"}],"updated_at":"2026-11-03T05:08:39.228431Z"}],"nvd":[{"id":"CVE-2026-55612","description":"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-\u003econtent_length` and `r-\u003etransfer_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.","status":"published","published":"2026-10-30T22:16:54.95Z","modified":"2026-11-02T19:35:33.347Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"low","assessor":"secondary"}],"cwes":["CWE-444"],"updated_at":"2026-11-03T00:02:42.364722Z"}],"osv":[{"id":"CVE-2026-55612","title":"uhttpd vulnerable to HTTP request smuggling via invalid chunk-length state reset","description":"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-\u003econtent_length` and `r-\u003etransfer_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.","status":"published","published":"2026-10-30T22:00:19.756Z","modified":"2026-11-04T07:03:26.907474692Z","cvss":[{"version":"3.1","score":3.7,"vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"low"}],"cwes":["CWE-444"],"updated_at":"2026-11-04T07:32:23.735279Z"}]}}