CVE-2026-87022
HIGHDescription
Improper handling of length parameter inconsistency vulnerability in Apache Tomcat allows WebSocket message smuggling when per-message-deflate is used. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.0.M1 through 9.0.121. The following versions were EOS at the time the CVE was created but are known to be affected: from 8.5.0 through 8.5.100, from 7.0.56 through 7.0.109. Other unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.1.22, which fix the issue.
How to fix
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Exploit Intelligence
Low risk: more likely to be exploited than 35% of all known CVEs.
References
Related Vulnerabilities
Other CWE-130 vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2025-14847 | High | 7.5 | 83% | KEV | Fix |
| CVE-2024-39614 | High | 7.5 | 29% | - | Fix |
| CVE-2021-36090 | High | 7.5 | 13% | - | Fix |
| CVE-2021-35516 | High | 7.5 | 12% | - | Fix |
| CVE-2021-35517 | High | 7.5 | 11% | - | Fix |
| CVE-2019-3862 | High | 7.3 | 7.9% | - | Fix |
Common questions
How do I fix CVE-2026-87022?
Upgrade tomcat10 on debian unstable to 10.1.60-1 or later.
Is CVE-2026-87022 being actively exploited?
Not that we know of. CVE-2026-87022 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.42% is the estimated probability that it will be exploited in the next 30 days. That is higher than 35% of all scored CVEs.
How severe is CVE-2026-87022?
CVE-2026-87022 has a CVSS v3 base score of 7.5, rated high. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.
What does CVE-2026-87022 affect?
Published advisories record a fix for tomcat10 (Debian). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.
Embed a live status badge for CVE-2026-87022
Markdown
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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-09-23.