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.
CVE-2026-3099
MEDIUMNVD 7.35.8▼Trending — 4 sources updated this week
EchelonGraph scoreMEDIUM confidence
Score 5.8 from GitHub Security Advisory published 2026-03-12. the CNA's CVSS baseline 5.8; sources differ by 0.0.
Triggered by: GitHub Security Advisory CVSS
Sources: cna:redhat, ghsa
5.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
- High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.3Exploit: None knownExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 7.3
- EG Score
- 5.8(medium)
- EG Risk
- 26(Track)EG Risk 26/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity58% × 45%Exploitation0% × 40%Automatability0% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
- 0%
- EPSS %ILE
- 28%
- KEV
- Not listed
Published
March 12, 2026
Last Modified
June 17, 2026
References (3)
- secalert@redhathttps://access.redhat.com/security/cve/CVE-2026-3099
- secalert@redhathttps://bugzilla.redhat.com/show_bug.cgi?id=2442232
- secalert@redhathttps://gitlab.gnome.org/GNOME/libsoup/-/issues/495
Vendor Advisories for CVE-2026-3099(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 7× in last 7d / 7× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-08-01 04:16 UTCEPSS rescore
- 2026-07-30 16:28 UTCEPSS rescore
- 2026-07-30 01:30 UTCEPSS rescore
- 2026-07-27 14:13 UTCEPSS rescore
- 2026-07-27 12:52 UTCEG score recompute
- 2026-07-27 12:52 UTCGHSA enrichment
- 2026-07-27 12:50 UTCOSV refresh
Frequently asked(5)
What is CVE-2026-3099?
CVE-2026-3099 is a medium vulnerability published on March 12, 2026. 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…
When was CVE-2026-3099 disclosed?
CVE-2026-3099 was first published in the National Vulnerability Database on March 12, 2026, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-3099 actively exploited?
CVE-2026-3099 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 71.8% of all scored CVEs.
What is the CVSS score of CVE-2026-3099?
CVE-2026-3099 has a CVSS v3 base score of 7.3 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 5.8.
How do I remediate CVE-2026-3099?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-3099, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-3099
Is Your Infrastructure Affected by CVE-2026-3099?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.