CVE-2026-12549: Gnome Libsoup

Medium severity, CVSS 4.8. EPSS: 0.4% chance of exploitation in the next 30 days.

The fix for CVE-2026-2443 was regressed by a subsequent rework commit that replaced specific overflow checks with a general signed comparison. When a client sends a Range request with a suffix length exceeding the content size, the resulting negative start value is not properly clamped, leading to malformed HTTP 206 responses and log flooding.

Affected products

• Gnome Libsoup: affected versions not specified
• Red Hat Enterprise Linux: version 6.0 only; version 7.0 only; version 8.0 only; version 9.0 only; version 10.0 only

Published 2026-06-22. Last modified 2026-07-08.