7.5

CVE-2026-77791: apache software foundation apache tomcat Uncontrolled Resource Consumption

CVSS: 7.5v3.1HighAwaiting analysis
AliasesUBUNTU-CVE-2026-77791DEBIAN-CVE-2026-77791
Published 23-09-2026Last modified 23-09-2026
Open JSON

Vulnerability summary

CVE-2026-77791 is a high (CVSS 7.5) Uncontrolled Resource Consumption vulnerability in apache software foundation apache tomcat. EPSS estimates a 0.53% chance of exploitation in the next 30 days, higher than 43.7% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (CVE.org)
EPSS score
0.53%
0%100%
Low · Change unavailable
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 10 · Related 7
MGASA-2026-0479OPENSUSE-SU-2026:11906-1OPENSUSE-SU-2026:11907-1OPENSUSE-SU-2026:11908-1OPENSUSE-SU-2026:21984-1RHSA-2026:68257

Timeline

  1. 23-09-2026
    PublishedVulnerability first disclosed.
  2. 23-09-2026
    Last modifiedVulnerability information updated.

Description

Uncontrolled Resource Consumption vulnerability in Apache Tomcat during sending of WebSocket close message enabled a DoS attack. This issue affects Apache Tomcat: from 11.0.0-M5 through 11.0.25, from 10.1.8 through 10.1.59, from 9.0.74 through 9.0.121. The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.88 through 8.5.100. Other unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.53%

Chance of exploitation in the next 30 days

Percentile

44%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

24-09-202619-10-2026
EPSS score
0.53%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Ubuntu6 products
  • tomcat10All versions (No fix recorded)
  • tomcat11All versions (No fix recorded)
  • tomcat6All versions (No fix recorded)
  • tomcat7All versions (No fix recorded)
  • tomcat8All versions (No fix recorded)
Debian3 products
  • tomcat10All versions (No fix recorded) | < 10.1.60-1
  • tomcat11All versions (No fix recorded)
  • tomcat9< 9.0.70-2
Apache software foundation1 product
  • apache tomcat≥ 11.0.0-M5, ≤ 11.0.25 | ≥ 10.1.8, ≤ 10.1.59 | ≥ 9.0.74, ≤ 9.0.121 | ≥ 8.5.88, ≤ 8.5.100

3 vendors · 10 products

References

8 links