CVE-2026-55955

MEDIUMPre-NVD 6.56.5—
EchelonGraph scoreMEDIUM 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(medium)
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
37%
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.

Affected Packages

(9 across 4 ecosystems)
Debian:13(3)
PackageVulnerable rangeFixed inDependents
tomcat1010.1.40-1 ... 10.1.55-1~deb13u1 (10 versions)——
tomcat1111.0.11-1 ... 11.0.6-1 (10 versions)——
tomcat9—9.0.70-2—
Debian:14(3)
PackageVulnerable rangeFixed inDependents
tomcat1010.1.40-1 ... 10.1.55-1~deb13u1 (10 versions)——
tomcat1111.0.11-1 ... 11.0.6-1 (9 versions)11.0.24-1—
tomcat9—9.0.70-2—
Debian:12(2)
PackageVulnerable rangeFixed inDependents
tomcat1010.1.10-1 ... 10.1.9-1 (36 versions)——
tomcat9—9.0.70-2—
Debian:11(1)
PackageVulnerable rangeFixed inDependents
tomcat99.0.43-1 ... 9.0.70-1 (28 versions)9.0.70-2—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 12× in last 7d / 54× 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.

Showing the most recent 100 of 217 total refreshes for this CVE.

  1. 2026-09-18 19:28 UTCEPSS rescore
  2. 2026-09-18 06:55 UTCEG score recompute
  3. 2026-09-18 06:55 UTCVendor advisory
  4. 2026-09-18 06:55 UTCGHSA enrichment
  5. 2026-09-17 19:31 UTCEPSS rescore
  6. 2026-09-16 14:08 UTCEPSS rescore
  7. 2026-09-16 05:15 UTCEPSS rescore
  8. 2026-09-15 03:11 UTCEPSS rescore
  9. 2026-09-14 00:50 UTCEG score recompute
  10. 2026-09-14 00:50 UTCVendor advisory
  11. 2026-09-14 00:50 UTCGHSA enrichment
  12. 2026-09-13 16:47 UTCEPSS rescore
  13. 2026-09-12 15:13 UTCEG score recompute
  14. 2026-09-12 15:13 UTCVendor advisory
  15. 2026-09-12 15:13 UTCGHSA enrichment
  16. 2026-09-11 14:53 UTCEPSS rescore
  17. 2026-09-10 09:35 UTCEPSS rescore
  18. 2026-09-08 22:01 UTCEPSS rescore
  19. 2026-09-07 16:01 UTCEPSS rescore
  20. 2026-09-06 14:39 UTCEG score recompute
  21. 2026-09-06 14:39 UTCVendor advisory
  22. 2026-09-06 14:39 UTCGHSA enrichment
  23. 2026-09-06 13:47 UTCEPSS rescore
  24. 2026-09-04 05:07 UTCEPSS rescore
  25. 2026-09-02 14:12 UTCEPSS rescore
Show 75 more
  1. 2026-09-01 13:54 UTCEPSS rescore
  2. 2026-09-01 04:40 UTCEPSS rescore
  3. 2026-08-30 19:17 UTCEPSS rescore
  4. 2026-08-30 18:23 UTCEG score recompute
  5. 2026-08-30 18:23 UTCVendor advisory
  6. 2026-08-30 18:23 UTCGHSA enrichment
  7. 2026-08-30 01:22 UTCEPSS rescore
  8. 2026-08-28 21:41 UTCEPSS rescore
  9. 2026-08-27 22:45 UTCEG score recompute
  10. 2026-08-27 22:45 UTCVendor advisory
  11. 2026-08-27 22:45 UTCGHSA enrichment
  12. 2026-08-27 14:25 UTCEPSS rescore
  13. 2026-08-26 14:46 UTCEPSS rescore
  14. 2026-08-25 13:49 UTCEPSS rescore
  15. 2026-08-24 12:39 UTCEG score recompute
  16. 2026-08-24 12:39 UTCVendor advisory
  17. 2026-08-24 12:39 UTCGHSA enrichment
  18. 2026-08-23 10:53 UTCEG score recompute
  19. 2026-08-23 10:53 UTCVendor advisory
  20. 2026-08-23 10:53 UTCGHSA enrichment
  21. 2026-08-23 00:19 UTCEPSS rescore
  22. 2026-08-22 09:09 UTCEG score recompute
  23. 2026-08-22 09:09 UTCVendor advisory
  24. 2026-08-22 09:09 UTCGHSA enrichment
  25. 2026-08-21 23:49 UTCEPSS rescore
  26. 2026-08-21 07:24 UTCEG score recompute
  27. 2026-08-21 07:24 UTCVendor advisory
  28. 2026-08-21 07:24 UTCGHSA enrichment
  29. 2026-08-20 22:55 UTCEPSS rescore
  30. 2026-08-20 05:40 UTCEG score recompute
  31. 2026-08-20 05:40 UTCVendor advisory
  32. 2026-08-20 05:40 UTCGHSA enrichment
  33. 2026-08-19 17:04 UTCEPSS rescore
  34. 2026-08-18 23:09 UTCEG score recompute
  35. 2026-08-18 23:09 UTCVendor advisory
  36. 2026-08-18 23:09 UTCGHSA enrichment
  37. 2026-08-18 13:48 UTCEPSS rescore
  38. 2026-08-17 13:47 UTCEPSS rescore
  39. 2026-08-17 11:53 UTCEG score recompute
  40. 2026-08-17 11:53 UTCVendor advisory
  41. 2026-08-17 11:53 UTCGHSA enrichment
  42. 2026-08-16 14:56 UTCEPSS rescore
  43. 2026-08-16 10:08 UTCEG score recompute
  44. 2026-08-16 10:08 UTCVendor advisory
  45. 2026-08-16 10:08 UTCGHSA enrichment
  46. 2026-08-16 02:14 UTCEPSS rescore
  47. 2026-08-15 08:24 UTCEG score recompute
  48. 2026-08-15 08:24 UTCVendor advisory
  49. 2026-08-15 08:24 UTCGHSA enrichment
  50. 2026-08-15 01:30 UTCEPSS rescore
  51. 2026-08-14 06:39 UTCEG score recompute
  52. 2026-08-14 06:39 UTCVendor advisory
  53. 2026-08-14 06:39 UTCGHSA enrichment
  54. 2026-08-13 22:00 UTCEPSS rescore
  55. 2026-08-13 04:54 UTCEG score recompute
  56. 2026-08-13 04:54 UTCVendor advisory
  57. 2026-08-13 04:54 UTCGHSA enrichment
  58. 2026-08-12 13:51 UTCEPSS rescore
  59. 2026-08-12 03:10 UTCEG score recompute
  60. 2026-08-12 03:10 UTCVendor advisory
  61. 2026-08-12 03:10 UTCGHSA enrichment
  62. 2026-08-11 01:25 UTCEG score recompute
  63. 2026-08-11 01:25 UTCVendor advisory
  64. 2026-08-11 01:25 UTCGHSA enrichment
  65. 2026-08-11 00:00 UTCEPSS rescore
  66. 2026-08-09 23:40 UTCEG score recompute
  67. 2026-08-09 23:40 UTCVendor advisory
  68. 2026-08-09 23:40 UTCGHSA enrichment
  69. 2026-08-09 13:46 UTCEPSS rescore
  70. 2026-08-08 21:56 UTCEG score recompute
  71. 2026-08-08 21:56 UTCVendor advisory
  72. 2026-08-08 21:56 UTCGHSA enrichment
  73. 2026-08-08 16:37 UTCEPSS rescore
  74. 2026-08-07 20:11 UTCEG score recompute
  75. 2026-08-07 20:11 UTCVendor advisory

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 62.6% 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

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-55955

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