6.9
MEDIUM CVSS 4.0
CVE-2026-55614
uhttpd vulnerable to HTTP request smuggling via case-sensitive Transfer-Encoding matching
Description

uhttpd is a small HTTP server. In unpatched repository snapshots, `client_parse_header()` in `client.c` lowercases header names but compares the `Transfer-Encoding` value to `chunked` using case-sensitive `strcmp`. A mixed-case transfer-coding token is accepted without enabling `r->transfer_chunked`, despite transfer-coding tokens being case-insensitive. On a keep-alive connection, the `chunked` POST body is left unread and request-shaped body bytes are parsed as another HTTP request, permitting HTTP request smuggling and boundary desynchronization. Commits ae015e099986ceace44975cb69629841a2d58d37 and 6641b050e5f7c7fd9ae92e8e119d6d6dfc6e9837 patch the issue.

INFO

Published Date :

Oct. 30, 2026, 10:16 p.m.

Last Modified :

Oct. 30, 2026, 10:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-55614 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 4.0 MEDIUM [email protected]
Solution
Apply the provided commits to patch the HTTP server's header parsing vulnerability.
  • Apply commit ae015e099986ceace44975cb69629841a2d58d37.
  • Apply commit 6641b050e5f7c7fd9ae92e8e119d6d6dfc6e9837.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-55614.

URL Resource
https://github.com/openwrt/uhttpd/commit/6641b050e5f7c7fd9ae92e8e119d6d6dfc6e9837
https://github.com/openwrt/uhttpd/commit/ae015e099986ceace44975cb69629841a2d58d37
https://github.com/openwrt/uhttpd/security/advisories/GHSA-mcfg-c4r7-pjpf
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-55614 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-55614 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-55614 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-55614 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Oct. 30, 2026

    Action Type Old Value New Value
    Added Description uhttpd is a small HTTP server. In unpatched repository snapshots, `client_parse_header()` in `client.c` lowercases header names but compares the `Transfer-Encoding` value to `chunked` using case-sensitive `strcmp`. A mixed-case transfer-coding token is accepted without enabling `r->transfer_chunked`, despite transfer-coding tokens being case-insensitive. On a keep-alive connection, the `chunked` POST body is left unread and request-shaped body bytes are parsed as another HTTP request, permitting HTTP request smuggling and boundary desynchronization. Commits ae015e099986ceace44975cb69629841a2d58d37 and 6641b050e5f7c7fd9ae92e8e119d6d6dfc6e9837 patch the issue.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-444
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/55xxx/CVE-2026-55614.json">CVE-2026-55614</a>
    Added Reference https://github.com/openwrt/uhttpd/commit/6641b050e5f7c7fd9ae92e8e119d6d6dfc6e9837
    Added Reference https://github.com/openwrt/uhttpd/commit/ae015e099986ceace44975cb69629841a2d58d37
    Added Reference https://github.com/openwrt/uhttpd/security/advisories/GHSA-mcfg-c4r7-pjpf
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.