Vulnerability 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->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.
CVSS Score
LOW
Related Weaknesses (CWE)
References
- https://github.com/openwrt/uhttpd/commit/34460b8211d676ef1b9f40d6b775c5e11293369
- https://github.com/openwrt/uhttpd/commit/b78f518478794e16ba3568fc1258e40bf3e8eb3
- https://github.com/openwrt/uhttpd/security/advisories/GHSA-p55c-rmhc-qfm5
FAQ
What is CVE-2026-55612?
CVE-2026-55612 is a vulnerability with a CVSS score of 3.7 (LOW). 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->conte...
How severe is CVE-2026-55612?
CVE-2026-55612 has been rated LOW with a CVSS base score of 3.7/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-55612?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.