CVE-2026-55612 (GCVE-0-2026-55612)

Vulnerability from cvelistv5 – Published: 2026-10-30 22:00 – Updated: 2026-11-02 18:09
VLAI
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` 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
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-02 17:03 UTC
CWE
  • CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7886 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
openwrt uhttpd Affected: >= b7c85a2819b3869279a669d5681f574824589c6c, < b78f518478794e16ba3568fc1258e40bf3e8eb3b
Affected: >= b7c85a2819b3869279a669d5681f574824589c6c, < 34460b8211d676ef1b9f40d6b775c5e112933690
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