HTTP Request Smuggling Vulnerability in uhttpd by OpenWRT
CVE-2026-55612

3.7LOW

Key Information:

Vendor

Openwrt

Status
Uhttpd
Vendor
CVE Published:
30 October 2026

What is CVE-2026-55612?

The uhttpd HTTP server in unpatched repository snapshots contains a vulnerability that allows HTTP request smuggling due to improper handling of chunked POST requests. Specifically, in the client_poll_post_data() function, invalid chunk-length handling leads to erroneous clearing of r->content_length and r->transfer_chunked. This results in unprocessed request bodies being parsed as separate HTTP requests over the same connection, compromising the integrity of request boundaries. Successful exploitation could enable attackers to manipulate the server's HTTP responses and affect other users' sessions.

Affected Version(s)

uhttpd >= b7c85a2819b3869279a669d5681f574824589c6c, < b78f518478794e16ba3568fc1258e40bf3e8eb3b < b7c85a2819b3869279a669d5681f574824589c6c, b78f518478794e16ba3568fc1258e40bf3e8eb3b

uhttpd >= b7c85a2819b3869279a669d5681f574824589c6c, < 34460b8211d676ef1b9f40d6b775c5e112933690 < b7c85a2819b3869279a669d5681f574824589c6c, 34460b8211d676ef1b9f40d6b775c5e112933690

References

https://github.com/openwrt/uhttpd/security/advisories/GHS...
x_refsource_CONFIRM
https://github.com/openwrt/uhttpd/commit/34460b8211d676ef...
x_refsource_MISC
https://github.com/openwrt/uhttpd/commit/b78f518478794e16...
x_refsource_MISC

CVSS V3.1

Score:
3.7
Severity:
LOW
Confidentiality:
None
Integrity:
Low
Availability:
None
Attack Vector:
Network
Attack Complexity:
High
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.