CVE-2026-55276

CRITICALPre-NVD 9.19.1—
EchelonGraph scoreHIGH confidence

Score 9.1 from GitHub Security Advisory (severity: CRITICAL) published 2026-06-29. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 9.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 4 sources updated this week
9.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 9.1Exploit: None knownExposed: 0

A fix is available — apply it.

Always-Incorrect Control Flow Implementation vulnerability in Apache Tomcat meant that special roles and empty authorisation constraints were not included when the effective web.xml was logged.

This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from 9.0.0.M1 through 9.0.118, from 8.5.0 through 8.5.100. Other versions that have reached end of support may also be affected.

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

CVSS v3
9.1
EG Score
9.1(high)
EG Risk
46(Track)
EG Risk 46/100SSVC: 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
Severity91% × 45%
Exploitation1% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
42%
KEV
Not listed

Published

June 29, 2026

Last Modified

July 2, 2026

Advisory Details (2)

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

oss-security - CVE-2026-55276: Apache Tomcat: Logged effective web.xml is incomplete

http://www.openwall.com/lists/oss-security/2026/06/29/23
generic
https://lists.apache.org/thread/jy09xjlzn6r2qwvqoph8vcmf959yq68v

Vendor Advisories for CVE-2026-55276(3)

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

Patch Availability(3)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntutomcat8-user (8.0.32-1ubuntu1.13+esm2) @ xenial2026-07-27ubuntu
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.

Additional Vendor Advisories

(1)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 22× in last 7d / 232× 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. 2026-07-27 10:44 UTCVendor advisory
  2. 2026-07-27 10:44 UTCGHSA enrichment
  3. 2026-07-27 06:36 UTCVendor advisory
  4. 2026-07-27 06:35 UTCGHSA enrichment
  5. 2026-07-27 02:37 UTCVendor advisory
  6. 2026-07-27 02:37 UTCGHSA enrichment
  7. 2026-07-26 22:38 UTCVendor advisory
  8. 2026-07-26 22:38 UTCGHSA enrichment
  9. 2026-07-26 18:38 UTCEG score recompute
  10. 2026-07-26 18:38 UTCVendor advisory
  11. 2026-07-26 18:38 UTCGHSA enrichment
  12. 2026-07-26 14:54 UTCEPSS rescore
  13. 2026-07-26 13:57 UTCEG score recompute
  14. 2026-07-26 13:57 UTCVendor advisory
  15. 2026-07-26 13:57 UTCGHSA enrichment
  16. 2026-07-25 14:18 UTCEPSS rescore
  17. 2026-07-24 14:18 UTCEPSS rescore
  18. 2026-07-23 14:18 UTCEPSS rescore
  19. 2026-07-23 03:20 UTCEG score recompute
  20. 2026-07-22 14:08 UTCEPSS rescore
  21. 2026-07-21 15:25 UTCEPSS rescore
  22. 2026-07-20 17:08 UTCEPSS rescore
  23. 2026-07-19 14:31 UTCEPSS rescore
  24. 2026-07-19 14:31 UTCEPSS rescore
  25. 2026-07-19 02:29 UTCEPSS rescore
Show 75 more
  1. 2026-07-18 10:04 UTCEPSS rescore
  2. 2026-07-17 03:56 UTCVendor advisory
  3. 2026-07-17 03:56 UTCGHSA enrichment
  4. 2026-07-16 23:58 UTCVendor advisory
  5. 2026-07-16 23:58 UTCGHSA enrichment
  6. 2026-07-16 20:00 UTCVendor advisory
  7. 2026-07-16 20:00 UTCGHSA enrichment
  8. 2026-07-16 17:03 UTCEPSS rescore
  9. 2026-07-16 16:02 UTCVendor advisory
  10. 2026-07-16 16:02 UTCGHSA enrichment
  11. 2026-07-16 11:34 UTCVendor advisory
  12. 2026-07-16 11:34 UTCGHSA enrichment
  13. 2026-07-16 07:36 UTCVendor advisory
  14. 2026-07-16 07:36 UTCGHSA enrichment
  15. 2026-07-16 03:38 UTCVendor advisory
  16. 2026-07-16 03:38 UTCGHSA enrichment
  17. 2026-07-15 23:40 UTCVendor advisory
  18. 2026-07-15 23:40 UTCGHSA enrichment
  19. 2026-07-15 19:42 UTCVendor advisory
  20. 2026-07-15 19:42 UTCGHSA enrichment
  21. 2026-07-15 16:57 UTCEPSS rescore
  22. 2026-07-15 16:57 UTCEPSS rescore
  23. 2026-07-15 15:44 UTCVendor advisory
  24. 2026-07-15 15:44 UTCGHSA enrichment
  25. 2026-07-15 11:46 UTCVendor advisory
  26. 2026-07-15 11:45 UTCGHSA enrichment
  27. 2026-07-15 07:45 UTCVendor advisory
  28. 2026-07-15 07:45 UTCGHSA enrichment
  29. 2026-07-15 03:42 UTCVendor advisory
  30. 2026-07-15 03:42 UTCGHSA enrichment
  31. 2026-07-15 02:00 UTCEPSS rescore
  32. 2026-07-15 02:00 UTCEPSS rescore
  33. 2026-07-14 23:35 UTCVendor advisory
  34. 2026-07-14 23:35 UTCGHSA enrichment
  35. 2026-07-14 19:26 UTCVendor advisory
  36. 2026-07-14 19:26 UTCGHSA enrichment
  37. 2026-07-14 15:12 UTCVendor advisory
  38. 2026-07-14 15:12 UTCGHSA enrichment
  39. 2026-07-14 11:14 UTCVendor advisory
  40. 2026-07-14 11:14 UTCGHSA enrichment
  41. 2026-07-14 07:14 UTCVendor advisory
  42. 2026-07-14 07:14 UTCGHSA enrichment
  43. 2026-07-14 03:16 UTCVendor advisory
  44. 2026-07-14 03:16 UTCGHSA enrichment
  45. 2026-07-13 23:19 UTCVendor advisory
  46. 2026-07-13 23:19 UTCGHSA enrichment
  47. 2026-07-13 22:31 UTCEPSS rescore
  48. 2026-07-13 19:20 UTCVendor advisory
  49. 2026-07-13 19:20 UTCGHSA enrichment
  50. 2026-07-13 15:22 UTCVendor advisory
  51. 2026-07-13 15:22 UTCGHSA enrichment
  52. 2026-07-13 11:24 UTCVendor advisory
  53. 2026-07-13 11:24 UTCGHSA enrichment
  54. 2026-07-13 07:26 UTCVendor advisory
  55. 2026-07-13 07:26 UTCGHSA enrichment
  56. 2026-07-13 06:13 UTCEPSS rescore
  57. 2026-07-13 06:13 UTCEPSS rescore
  58. 2026-07-13 03:28 UTCVendor advisory
  59. 2026-07-13 03:27 UTCGHSA enrichment
  60. 2026-07-12 23:29 UTCVendor advisory
  61. 2026-07-12 23:28 UTCGHSA enrichment
  62. 2026-07-12 19:30 UTCVendor advisory
  63. 2026-07-12 19:30 UTCGHSA enrichment
  64. 2026-07-12 15:32 UTCVendor advisory
  65. 2026-07-12 15:31 UTCGHSA enrichment
  66. 2026-07-12 11:32 UTCVendor advisory
  67. 2026-07-12 11:32 UTCGHSA enrichment
  68. 2026-07-12 07:34 UTCVendor advisory
  69. 2026-07-12 07:34 UTCGHSA enrichment
  70. 2026-07-12 05:46 UTCEPSS rescore
  71. 2026-07-12 03:36 UTCVendor advisory
  72. 2026-07-12 03:36 UTCGHSA enrichment
  73. 2026-07-11 23:37 UTCVendor advisory
  74. 2026-07-11 23:37 UTCGHSA enrichment
  75. 2026-07-11 19:39 UTCVendor advisory

Frequently asked(5)

What is CVE-2026-55276?
CVE-2026-55276 is a critical vulnerability published on June 29, 2026. Always-Incorrect Control Flow Implementation vulnerability in Apache Tomcat meant that special roles and empty authorisation constraints were not included when the effective web.xml was logged. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.22, from 10.1.0-M1 through 10.1.55, from…
When was CVE-2026-55276 disclosed?
CVE-2026-55276 was first published in the National Vulnerability Database on June 29, 2026, with the most recent update on July 2, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-55276 actively exploited?
CVE-2026-55276 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 57.6% of all scored CVEs.
What is the CVSS score of CVE-2026-55276?
CVE-2026-55276 has a CVSS v3.1 base score of 9.1 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-55276?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-55276, 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.

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