How severe is CVE-2026-24880?

CVE-2026-24880 has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2026-24880?

CVE-2026-24880 affects the following packages: org.apache.tomcat:tomcat-coyote (Maven), org.apache.tomcat:tomcat-coyote (Maven), org.apache.tomcat:tomcat-coyote (Maven), org.apache.tomcat.embed:tomcat-embed-core (Maven), org.apache.tomcat.embed:tomcat-embed-core (Maven), org.apache.tomcat.embed:tomcat-embed-core (Maven). Ecosystems affected: Maven.

How do I fix CVE-2026-24880?

Update org.apache.tomcat:tomcat-coyote to 9.0.116 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-24880 is resolved across your whole dependency graph.

How do I detect CVE-2026-24880 in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.tomcat:tomcat-coyote, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-24880 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Is CVE-2026-24880 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-24880 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-24880?

CVE-2026-24880 has an EPSS (Exploit Prediction Scoring System) score of 0.7%, placing it in the 54th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-24880?

CVE-2026-24880 is classified as CWE-444 (CWE-444). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-24880 published, and has it been updated?

CVE-2026-24880 was published on April 9, 2026 and was last updated on October 29, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

☕

☕ Maven

Not in CISA KEV

HIGH severity

CVE-2026-24880 — tomcat-coyote

HIGHFix: apache/tomcat@1b586d6

CVE-2026-24880 is a high-severity (CVSS 7.5) CWE-444 vulnerability in org.apache.tomcat:tomcat-coyote. A fix is available for org.apache.tomcat:tomcat-coyote — see the affected versions and patch details below.

Apache Tomcat: Request smuggling via invalid chunk extension

Also known asBIT-tomcat-2026-24880GHSA-563x-q5rq-57qp

Published

Apr 9, 2026

Updated

Oct 29, 2026

Affected

6 pkgs

Patched

6 / 6

Exploits

None indexed

Exploitation data as of Nov 7, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-24880.

EPSS Exploitation Probability

via FIRST.org ↗

0.7%probability of exploitation in next 30 days

Lower Risk+0.01%

Lower risk than most CVEs54th percentile — riskier than 54% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

6 pkgs affected

☕org.apache.tomcat:tomcat-coyote☕org.apache.tomcat:tomcat-coyote☕org.apache.tomcat:tomcat-coyote☕org.apache.tomcat.embed:tomcat-embed-core☕org.apache.tomcat.embed:tomcat-embed-core☕org.apache.tomcat.embed:tomcat-embed-core

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.

Description

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') vulnerability in Apache Tomcat via invalid chunk extension.

This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.18, from 10.1.0-M1 through 10.1.52, from 9.0.0.M1 through 9.0.115, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Other, unsupported versions may also be affected.

Users are recommended to upgrade to version 11.0.20, 10.1.52 or 9.0.116, which fix the issue.

Affected Packages

6 total 6 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`org.apache.tomcat:tomcat-coyote`	≥ 7.0.0&&< 9.0.116	9.0.116`org.apache.tomcat:tomcat-coyote:9.0.116`
☕Maven	`org.apache.tomcat:tomcat-coyote`	≥ 10.1.0-M1&&< 10.1.52	10.1.52`org.apache.tomcat:tomcat-coyote:10.1.52`
☕Maven	`org.apache.tomcat:tomcat-coyote`	≥ 11.0.0-M1&&< 11.0.20	11.0.20`org.apache.tomcat:tomcat-coyote:11.0.20`
☕Maven	`org.apache.tomcat.embed:tomcat-embed-core`	≥ 7.0.0&&< 9.0.116	9.0.116`org.apache.tomcat.embed:tomcat-embed-core:9.0.116`
☕Maven	`org.apache.tomcat.embed:tomcat-embed-core`	≥ 10.1.0-M1&&< 10.1.52	10.1.52`org.apache.tomcat.embed:tomcat-embed-core:10.1.52`
☕Maven	`org.apache.tomcat.embed:tomcat-embed-core`	≥ 11.0.0-M1&&< 11.0.20	11.0.20`org.apache.tomcat.embed:tomcat-embed-core:11.0.20`

Affected Products

1 product · 3 configurations

Application

tomcatapache

≥ 11.0.0 && < 11.0.20

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.tomcat:tomcat-coyote, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.apache.tomcat:tomcat-coyote to 9.0.116 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-24880 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatLow

This vulnerability has a Low impact. A flaw in Apache Tomcat allows for HTTP Request/Response Smuggling through invalid chunk extensions. This could enable a remote attacker to bypass security controls or poison caches by manipulating HTTP request processing. This affects Red Hat Enterprise Linux and Red Hat JBoss Web…

Workaround published by Red Hat

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.

Source: Red Hat security advisory for CVE-2026-24880 (CC BY 4.0)

Product	Fixed in	Advisory
Red Hat Enterprise Linux 10	`tomcat9-1:9.0.117-1.el10_2`	RHSA-2026:25341
Red Hat Enterprise Linux 10.0 Extended Update Support	`tomcat9-1:9.0.120-1.el10_0`	RHSA-2026:67163
Red Hat Enterprise Linux 8	`tomcat-1:9.0.120-1.el8_10`	RHSA-2026:68677
Red Hat Enterprise Linux 8.8 Telecommunications Update Service	`tomcat-1:9.0.120-1.el8_8`	RHSA-2026:68680
Red Hat Enterprise Linux 9	`tomcat-1:9.0.117-1.el9_8`	RHSA-2026:26323
Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions	`tomcat-1:9.0.120-1.el9_2`	RHSA-2026:68678
Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions	`tomcat-1:9.0.120-1.el9_4`	RHSA-2026:68679
Red Hat Enterprise Linux 9.6 Extended Update Support	`tomcat-1:9.0.120-1.el9_6`	RHSA-2026:68659

Frequently Asked Questions

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') vulnerability in Apache Tomcat via invalid chunk extension. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.18, from 10.1.0-M1 through 10.1.52, from 9.0.0.M1 through 9.0.115, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Other, unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.20, 10.1.52 or 9.0.116, which fix the issue.

O3 Security · Impact-Aware SCA

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