Description
A flaw was found in Libsoup. The server-side digest authentication implementation in the SoupAuthDomainDigest class does not properly track issued nonces or enforce the required incrementing nonce-count (nc) attribute. This vulnerability allows a remote attacker to capture a single valid authentication header and replay it repeatedly. Consequently, the attacker can bypass authentication and gain unauthorized access to protected resources, impersonating the legitimate user.
Affected products
gnome: libsoup; redhat: enterprise linux
References3
- gitlab.gnome.org/GNOME/libsoup/-/issues/495 ExploitIssue TrackingThird Party Advisory
- access.redhat.com/security/cve/CVE-2026-3099 Third Party Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2442232 Issue TrackingThird Party Advisory
Metrics
- CVSS 3.1
-
7.3
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L - EPSS — exploit probability
- 0% percentile: 37 · as of 12 November 2026
- CWE
- CWE-323
Could this be exploited in your environment?
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