CVE-2026-55955

MEDIUMPre-NVD 6.56.5—
EchelonGraph scoreHIGH confidence

Score 6.5 from GitHub Security Advisory published 2026-06-29. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 6.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 4 sources updated this week
6.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.5Exploit: None knownExposed: 0

A fix is available — apply it.

Improper Authentication vulnerability in Apache Tomcat allowed a replay attack against the EncryptionInterceptor in the cluster component.

This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from 9.0.13 through 9.0.18, from 8.5.38 through 8.5.100, from 7.0.100 through 7.0.109.

Users are recommended to upgrade to version 11.0.23, 10.1.56, 9.0.119, which fixes the issue.

CVSS v3
6.5
EG Score
6.5(high)
EG Risk
34(Track)
EG Risk 34/100SSVC: 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
Severity65% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
38%
KEV
Not listed

Published

June 29, 2026

Last Modified

July 10, 2026

Advisory Details (2)

Auto-updated Jun 30, 2026
No patch confirmed yet.
generic

oss-security - CVE-2026-55955: Apache Tomcat: EncryptInterceptor not protected against replay attacks

http://www.openwall.com/lists/oss-security/2026/06/29/24
generic
https://lists.apache.org/thread/g4p5sf45p3f9r011pwqs9r54yd64s106

Vendor Advisories for CVE-2026-55955(3)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(2)

Vendor / EcosystemFixed in / PatchReleasedSource
redhattomcat11-main-11.0.23-0.1.hum12026-06-29redhat
redhattomcat10-main-10.1.56-1.hum12026-06-24redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 11× in last 7d / 77× 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. 2026-07-26 14:54 UTCEPSS rescore
  2. 2026-07-26 13:57 UTCEG score recompute
  3. 2026-07-26 13:57 UTCVendor advisory
  4. 2026-07-26 13:57 UTCGHSA enrichment
  5. 2026-07-25 14:18 UTCEPSS rescore
  6. 2026-07-24 14:18 UTCEPSS rescore
  7. 2026-07-23 14:18 UTCEPSS rescore
  8. 2026-07-23 03:20 UTCEG score recompute
  9. 2026-07-22 14:08 UTCEPSS rescore
  10. 2026-07-21 15:25 UTCEPSS rescore
  11. 2026-07-20 17:08 UTCEPSS rescore
  12. 2026-07-19 14:31 UTCEPSS rescore
  13. 2026-07-19 14:31 UTCEPSS rescore
  14. 2026-07-19 02:29 UTCEPSS rescore
  15. 2026-07-18 10:04 UTCEPSS rescore
  16. 2026-07-16 17:03 UTCEPSS rescore
  17. 2026-07-16 16:02 UTCVendor advisory
  18. 2026-07-16 16:02 UTCGHSA enrichment
  19. 2026-07-15 16:57 UTCEPSS rescore
  20. 2026-07-15 16:57 UTCEPSS rescore
  21. 2026-07-15 13:43 UTCVendor advisory
  22. 2026-07-15 13:42 UTCGHSA enrichment
  23. 2026-07-15 02:00 UTCEPSS rescore
  24. 2026-07-15 02:00 UTCEPSS rescore
  25. 2026-07-14 11:56 UTCVendor advisory
Show 52 more
  1. 2026-07-14 11:56 UTCGHSA enrichment
  2. 2026-07-13 22:31 UTCEPSS rescore
  3. 2026-07-13 10:10 UTCVendor advisory
  4. 2026-07-13 10:10 UTCGHSA enrichment
  5. 2026-07-13 06:13 UTCEPSS rescore
  6. 2026-07-13 06:13 UTCEPSS rescore
  7. 2026-07-12 08:12 UTCVendor advisory
  8. 2026-07-12 08:12 UTCGHSA enrichment
  9. 2026-07-12 05:46 UTCEPSS rescore
  10. 2026-07-11 08:27 UTCEPSS rescore
  11. 2026-07-11 08:27 UTCEPSS rescore
  12. 2026-07-11 06:27 UTCVendor advisory
  13. 2026-07-11 06:27 UTCGHSA enrichment
  14. 2026-07-10 04:43 UTCVendor advisory
  15. 2026-07-10 04:43 UTCGHSA enrichment
  16. 2026-07-09 19:10 UTCEPSS rescore
  17. 2026-07-09 19:10 UTCEPSS rescore
  18. 2026-07-09 02:56 UTCVendor advisory
  19. 2026-07-09 02:56 UTCGHSA enrichment
  20. 2026-07-08 15:16 UTCEPSS rescore
  21. 2026-07-08 15:16 UTCEPSS rescore
  22. 2026-07-08 01:11 UTCVendor advisory
  23. 2026-07-08 01:11 UTCGHSA enrichment
  24. 2026-07-07 13:46 UTCEPSS rescore
  25. 2026-07-07 13:46 UTCEPSS rescore
  26. 2026-07-06 23:26 UTCVendor advisory
  27. 2026-07-06 23:26 UTCGHSA enrichment
  28. 2026-07-06 16:27 UTCEPSS rescore
  29. 2026-07-06 16:27 UTCEPSS rescore
  30. 2026-07-06 02:23 UTCEPSS rescore
  31. 2026-07-06 02:23 UTCEPSS rescore
  32. 2026-07-05 21:41 UTCVendor advisory
  33. 2026-07-05 21:41 UTCGHSA enrichment
  34. 2026-07-05 02:31 UTCEPSS rescore
  35. 2026-07-05 02:30 UTCEPSS rescore
  36. 2026-07-04 19:56 UTCVendor advisory
  37. 2026-07-04 19:56 UTCGHSA enrichment
  38. 2026-07-04 06:31 UTCEPSS rescore
  39. 2026-07-04 06:31 UTCEPSS rescore
  40. 2026-07-03 18:11 UTCVendor advisory
  41. 2026-07-03 18:11 UTCGHSA enrichment
  42. 2026-07-02 16:27 UTCEG score recompute▲ 6.50
  43. 2026-07-02 16:27 UTCVendor advisory
  44. 2026-07-02 16:27 UTCGHSA enrichment
  45. 2026-07-01 15:07 UTCEPSS rescore
  46. 2026-06-30 23:22 UTCEPSS rescore
  47. 2026-06-30 14:32 UTCNVD updateCVSS v3 → 6.5 · severity → MEDIUM
  48. 2026-06-30 00:21 UTCNVD update
  49. 2026-06-29 22:44 UTCMITRE cvelistV5
  50. 2026-06-29 21:26 UTCNVD update
  51. 2026-06-29 20:57 UTCEG score recompute
  52. 2026-06-29 20:57 UTCMITRE cvelistV5first tracked

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-55955?
CVE-2026-55955 is a medium vulnerability published on June 29, 2026. Improper Authentication vulnerability in Apache Tomcat allowed a replay attack against the EncryptionInterceptor in the cluster component. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from 9.0.13 through 9.0.18, from 8.5.38 through 8.5.100, from…
When was CVE-2026-55955 disclosed?
CVE-2026-55955 was first published in the National Vulnerability Database on June 29, 2026, with the most recent update on July 10, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-55955 actively exploited?
CVE-2026-55955 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 62.1% of all scored CVEs.
What is the CVSS score of CVE-2026-55955?
CVE-2026-55955 has a CVSS v3.1 base score of 6.5 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-55955?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-55955, 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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