9.1

CVE-2026-86350: apache software foundation apache tomcat HTTP Request/Response Smuggling

CVSS: 9.1v3.1CriticalAwaiting analysis
AliasesUBUNTU-CVE-2026-86350DEBIAN-CVE-2026-86350
Published 23-09-2026Last modified 23-09-2026
Open JSON

Vulnerability summary

CVE-2026-86350 is a critical (CVSS 9.1) HTTP Request/Response Smuggling vulnerability in apache software foundation apache tomcat. EPSS estimates a 0.31% chance of exploitation in the next 30 days, higher than 22.7% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.1/10
010
Critical · v3.1 (CVE.org)
EPSS score
0.31%
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

Inconsistent interpretation of HTTP/2 requests ('HTTP Request/Response smuggling') vulnerability in Apache Tomcat caused by a regression in fix for CVE-2026-41293 can trigger request header mix-up. This issue affects Apache Tomcat: from 11.0.22 through 11.0.25, from 10.1.55 through 10.1.59, from 9.0.118 through 9.0.121. 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

0.31%

Chance of exploitation in the next 30 days

Percentile

23%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

24-09-202619-10-2026
EPSS score
0.31%

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≥ 11.0.22, ≤ 11.0.25 | ≥ 10.1.55, ≤ 10.1.59 | ≥ 9.0.118, ≤ 9.0.121

3 vendors · 10 products

References

7 links