CVE-2026-38969

HIGH

Published Jul 2, 2026 Modified Jul 6, 2026 CWE-444

Description

ruby webrick through v1.9.2 WEBrick reparses trailer Content-Length into canonical request state, enabling request smuggling.

Is your site exposed to CVE-2026-38969?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

EPSS — Exploit Prediction

0.0035

Probability of exploitation

0.27%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-444 CWE-444

References

Other References

https://github.com/ruby/webrick/issues/198 https://github.com/ruby/webrick/pull/199 https://github.com/ruby/webrick/issues/198

Frequently Asked Questions

What is CVE-2026-38969? +

ruby webrick through v1.9.2 WEBrick reparses trailer Content-Length into canonical request state, enabling request smuggling. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2026-38969? +

CVE-2026-38969 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0035, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-38969? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2025-1867

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') vulnerability in ithewei libhv allows HTTP Response Smuggling.This issue affects libhv: through …

CVE-2026-55614

uhttpd is a small HTTP server. In unpatched repository snapshots, `client_parse_header()` in `client.c` lowercases header names but compares the `Transfer-Encoding` …

CVE-2026-82672

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') vulnerability in elixir-mint mint allows a malicious HTTP/1 server to desynchronize a …

CVE-2026-118264

Echo is a Go web framework. From 4.0.0 until 4.16.1 and 5.4.1, Echo's Proxy middleware selects a raw tunnel from …

CVE-2026-55458

Caddy is an extensible server platform that uses TLS by default. Prior to 2.11.5, the reverse proxy's finalizeResponse method in …

CVE-2026-105298

Summary Before version 0.9.0, Pingora accepted HTTP/2 requests whose Host header differed from the :authority pseudo-header. Request filters, cache keys, …