CVE-2026-3099

HIGHNVD 7.37.3—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.3 under NVD CVSS v3. EPSS exploit probability: 0.4%, top 71% of all CVEs by exploit prediction. GitHub Security Advisory enrichment pending alignment with NVD CVSS.

Triggered by: NVD CVSS baseline
Sources: epss, ghsa, nvd
7.3EG
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.

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.

CVSS v3
7.3
EG Score
7.3(medium)
EG Risk
33(Track)
EG Risk 33/100SSVC: 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 computed
Severity73% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
29%
KEV
Not listed

Published

March 12, 2026

Last Modified

June 17, 2026

Advisory Details (3)

Auto-updated Aug 2, 2026
Patch available. Sources: redhat.
generic

(CVE-2026-3099) (#YWH-PGM9867-162) Broken Authentication: Digest Nonce Replay via Missing Nonce-Count Enforcement (#495) · Issues · GNOME / libsoup · GitLab

https://gitlab.gnome.org/GNOME/libsoup/-/issues/495
redhat

2442232 – (CVE-2026-3099) CVE-2026-3099 libsoup: Libsoup: Authentication bypass via digest authentication replay attack

https://bugzilla.redhat.com/show_bug.cgi?id=2442232
redhat Patch Available

cve-details

https://access.redhat.com/security/cve/CVE-2026-3099

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.

Affected Packages

(6 across 4 ecosystems)
Debian:12(2)
PackageVulnerable rangeFixed inDependents
libsoup2.42.74.3-1 ... 2.74.3-9 (16 versions)——
libsoup33.2.2-2 ... 3.6.6-1 (35 versions)——
Debian:13(2)
PackageVulnerable rangeFixed inDependents
libsoup2.42.74.3-10.1, 2.74.3-11——
libsoup33.6.5-3 ... 3.6.6-1 (8 versions)——
Debian:11(1)
PackageVulnerable rangeFixed inDependents
libsoup2.42.72.0-2 ... 2.74.3-9 (28 versions)——
Debian:14(1)
PackageVulnerable rangeFixed inDependents
libsoup33.6.5-3 ... 3.6.6-1 (8 versions)——

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 8× in last 7d / 28× 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.

  1. 2026-09-18 19:28 UTCEPSS rescore
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-17 19:30 UTCEPSS rescore
  4. 2026-09-16 14:08 UTCEPSS rescore
  5. 2026-09-16 05:15 UTCEPSS rescore
  6. 2026-09-15 03:11 UTCEPSS rescore
  7. 2026-09-13 16:47 UTCEPSS rescore
  8. 2026-09-12 15:01 UTCEPSS rescore
  9. 2026-09-11 14:53 UTCEPSS rescore
  10. 2026-09-11 09:37 UTCEPSS rescore
  11. 2026-09-10 09:34 UTCEPSS rescore
  12. 2026-09-08 22:00 UTCEPSS rescore
  13. 2026-09-07 16:01 UTCEPSS rescore
  14. 2026-09-06 13:47 UTCEPSS rescore
  15. 2026-09-04 05:06 UTCEPSS rescore
  16. 2026-09-02 19:40 UTCOSV refresh
  17. 2026-09-02 14:12 UTCEPSS rescore
  18. 2026-09-01 13:53 UTCEPSS rescore
  19. 2026-09-01 04:39 UTCEPSS rescore
  20. 2026-08-30 19:17 UTCEPSS rescore
  21. 2026-08-30 01:22 UTCEPSS rescore
  22. 2026-08-28 21:41 UTCEPSS rescore
  23. 2026-08-27 14:25 UTCEPSS rescore
  24. 2026-08-26 14:46 UTCEPSS rescore
  25. 2026-08-25 13:49 UTCEPSS rescore
Show 55 more
  1. 2026-08-23 00:19 UTCEPSS rescore
  2. 2026-08-21 23:49 UTCEPSS rescore
  3. 2026-08-20 22:55 UTCEPSS rescore
  4. 2026-08-19 17:03 UTCEPSS rescore
  5. 2026-08-18 13:48 UTCEPSS rescore
  6. 2026-08-17 13:47 UTCEPSS rescore
  7. 2026-08-16 14:56 UTCEPSS rescore
  8. 2026-08-16 11:47 UTCEG score recompute
  9. 2026-08-16 11:47 UTCGHSA enrichment
  10. 2026-08-16 02:14 UTCEPSS rescore
  11. 2026-08-15 01:30 UTCEPSS rescore
  12. 2026-08-14 20:09 UTCGHSA enrichment
  13. 2026-08-14 07:45 UTCEG score recompute
  14. 2026-08-14 07:45 UTCGHSA enrichment
  15. 2026-08-13 22:00 UTCEPSS rescore
  16. 2026-08-12 22:50 UTCEG score recompute
  17. 2026-08-12 22:50 UTCGHSA enrichment
  18. 2026-08-12 13:51 UTCEPSS rescore
  19. 2026-08-11 21:44 UTCEG score recompute
  20. 2026-08-11 21:44 UTCGHSA enrichment
  21. 2026-08-11 13:43 UTCEPSS rescore
  22. 2026-08-11 04:54 UTCEG score recompute
  23. 2026-08-11 04:54 UTCGHSA enrichment
  24. 2026-08-11 00:00 UTCEPSS rescore
  25. 2026-08-10 08:11 UTCGHSA enrichment
  26. 2026-08-09 19:48 UTCEG score recompute
  27. 2026-08-09 19:48 UTCGHSA enrichment
  28. 2026-08-09 13:46 UTCEPSS rescore
  29. 2026-08-09 07:26 UTCEG score recompute
  30. 2026-08-09 07:26 UTCGHSA enrichment
  31. 2026-08-08 16:37 UTCEPSS rescore
  32. 2026-08-08 06:32 UTCGHSA enrichment
  33. 2026-08-07 18:09 UTCEG score recompute
  34. 2026-08-07 18:09 UTCGHSA enrichment
  35. 2026-08-06 19:51 UTCEG score recompute
  36. 2026-08-06 19:51 UTCGHSA enrichment
  37. 2026-08-06 13:46 UTCEPSS rescore
  38. 2026-08-06 01:57 UTCEG score recompute
  39. 2026-08-06 01:57 UTCGHSA enrichment
  40. 2026-08-05 19:17 UTCEPSS rescore
  41. 2026-08-04 15:10 UTCEPSS rescore
  42. 2026-08-04 10:38 UTCEPSS rescore
  43. 2026-08-04 01:15 UTCEG score recompute
  44. 2026-08-04 01:14 UTCGHSA enrichment
  45. 2026-08-03 10:36 UTCEPSS rescore
  46. 2026-08-02 17:24 UTCEG score recompute▲ 1.50
  47. 2026-08-02 17:24 UTCGHSA enrichment
  48. 2026-08-02 02:27 UTCEPSS rescore
  49. 2026-08-01 04:16 UTCEPSS rescore
  50. 2026-07-30 16:28 UTCEPSS rescore
  51. 2026-07-30 01:30 UTCEPSS rescore
  52. 2026-07-27 14:13 UTCEPSS rescore
  53. 2026-07-27 12:52 UTCEG score recompute
  54. 2026-07-27 12:52 UTCGHSA enrichment
  55. 2026-07-27 12:50 UTCOSV refresh

Frequently asked(5)

What is CVE-2026-3099?
CVE-2026-3099 is a high 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 70.8% 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).
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

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