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
6.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 6.5Exploit: None knownExposed services: Not assessed

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
6.5MEDIUMmedium confidence
EG Risk
34
EG Risk 34/100

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%
EPSS PROB
0.4%
EPSS %ILE
35th
KEV
Not listed

Published

June 29, 2026

Last Modified

July 10, 2026

Advisory Details (2)

Auto-updated Jun 30, 2026
Patch available.
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(11)

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 / EcosystemFix (by version range) / 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 rangeFix by version rangeDependents
tomcat1010.1.40-1 ... 10.1.60-1 (11 versions)
  • every version on: no fix on record
—
tomcat1111.0.11-1 ... 11.0.6-1 (10 versions)
  • every version on: no fix on record
—
tomcat9—
  • every version up to 9.0.70-2: fixed in 9.0.70-2
—
Debian:14(3)
PackageVulnerable rangeFix by version rangeDependents
tomcat1010.1.40-1 ... 10.1.55-1~deb13u1 (10 versions)
  • every version up to 10.1.60-1: fixed in 10.1.60-1
—
tomcat1111.0.11-1 ... 11.0.6-1 (9 versions)
  • every version up to 11.0.24-1: fixed in 11.0.24-1
—
tomcat9—
  • every version up to 9.0.70-2: fixed in 9.0.70-2
—
Debian:12(2)
PackageVulnerable rangeFix by version rangeDependents
tomcat1010.1.10-1 ... 10.1.9-1 (37 versions)
  • every version on: no fix on record
—
tomcat9—
  • every version up to 9.0.70-2: fixed in 9.0.70-2
—
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
tomcat99.0.43-1 ... 9.0.70-1 (28 versions)
  • every version up to 9.0.70-2: fixed in 9.0.70-2
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 38× 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 232 total refreshes for this CVE.

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

Related CVEs(same product + 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 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 0.4% probability of exploitation in the next 30 days (35th percentile of EPSS-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?
A fix for CVE-2026-55955 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-55955 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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