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
39%
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 25× in last 7d / 99× 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 167 total refreshes for this CVE.

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

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 61.3% 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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