CVE-2026-2708

Description

A request smuggling vulnerability exists in libsoup's HTTP/1 header parsing logic. The soup_message_headers_append_common() function in libsoup/soup-message-headers.c unconditionally appends each header value without validating for duplicate or conflicting Content-Length fields. This allows an attacker to send HTTP requests containing multiple Content-Length headers with differing values.

CVSS v3.1 Score

3.7

LOW

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

EPSS — Exploit Prediction

0.0004

Probability of exploitation

0.11%

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

Affected Products

Vendor	Product	Versions
gnome	libsoup	All
redhat	enterprise_linux	All
redhat	enterprise_linux	All
redhat	enterprise_linux	All
redhat	enterprise_linux	All
redhat	enterprise_linux	All

References

Advisories & Patches

https://access.redhat.com/security/cve/CVE-2026-2708 https://bugzilla.redhat.com/show_bug.cgi?id=2440743 https://gitlab.gnome.org/GNOME/libsoup/-/issues/500

Exploits

https://gitlab.gnome.org/GNOME/libsoup/-/issues/500

Other References

https://gitlab.gnome.org/GNOME/libsoup/-/merge_requests/513

Frequently Asked Questions

What is CVE-2026-2708? +

A request smuggling vulnerability exists in libsoup's HTTP/1 header parsing logic. The soup_message_headers_append_common() function in libsoup/soup-message-headers.c unconditionally appends each header value without validating for duplicate or conflicting Content-Length fields. This allows an attacker to send HTTP requests containing multiple Content-Length headers with differing values. It has a CVSS v3.1 base score of 3.7 (LOW).

How severe is CVE-2026-2708? +

CVE-2026-2708 has a CVSS v3.1 score of 3.7 out of 10, rated LOW. This is a low-severity vulnerability with limited impact. The EPSS score is 0.0004, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-2708? +

CVE-2026-2708 affects products from gnome, redhat, specifically: enterprise_linux, libsoup. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-2708? +

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.

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