Cyber Resilience

CVE-2023-46589

Apache Tomcat 8.5.0 – 8.5.96

Published
28 November 2023
Modified
07 August 2025
Patch / advisory
View advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
EPSS Score 0.027 84th percentile
Risk Priority 80 floored blend · peak EPSS

Summary

CVE-2023-46589 is a high-severity HTTP Request/Response Smuggling (CWE-444) vulnerability in Apache Tomcat. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 16% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

Apache Tomcat contains an improper input validation vulnerability (CWE-444) affecting versions 11.0.0-M1 through 11.0.0-M10, 10.1.0-M1 through 10.1.15, 9.0.0-M1 through 9.0.82, and 8.5.0 through 8.5.95, along with certain older end-of-life releases. The flaw stems from incorrect parsing of HTTP trailer headers that exceed the configured size limit, allowing a single request to be misinterpreted as multiple requests.

An unauthenticated remote attacker can exploit the issue over the network by supplying a malicious trailer header in an HTTP request. When Tomcat operates behind a reverse proxy, this can enable request smuggling attacks that achieve high-integrity impacts such as bypassing access controls or cache poisoning, consistent with the CVSS 7.5 rating.

Apache project advisories direct users to upgrade to 11.0.0-M11, 10.1.16, 9.0.83, or 8.5.96 or later to resolve the parsing error. Coordinated notices from Debian LTS and NetApp similarly reference these patched releases and the associated Apache mailing-list announcements.

The EPSS score reached a peak of 0.5951 with a current value of 0.5316.

OWASP Top 10 for Web (2025)

A06:2025 Insecure Design

EU & UK References

Vulnerability Data

Improper Input Validation vulnerability in Apache Tomcat.Tomcat from 11.0.0-M1 through 11.0.0-M10, from 10.1.0-M1 through 10.1.15, from 9.0.0-M1 through 9.0.82 and from 8.5.0 through 8.5.95 did not correctly parse HTTP trailer headers. A trailer header that exceeded the header size limit…

more

could cause Tomcat to treat a single request as multiple requests leading to the possibility of request smuggling when behind a reverse proxy. Older, EOL versions may also be affected. Users are recommended to upgrade to version 11.0.0-M11 onwards, 10.1.16 onwards, 9.0.83 onwards or 8.5.96 onwards, which fix the issue.

CWE(s)
CWE-444

Related Threats

MITRE ATT&CK Enterprise Techniques

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-24880Same product: Apache Tomcat
CVE-2026-55957Same product: Apache Tomcat
CVE-2026-59083Same product: Apache Tomcat
CVE-2025-55752Same product: Apache Tomcat
CVE-2025-46701Same product: Apache Tomcat
CVE-2026-43513Same product: Apache Tomcat
CVE-2025-49125Same product: Apache Tomcat
CVE-2026-34483Same product: Apache Tomcat
CVE-2025-31651Same product: Apache Tomcat
CVE-2025-52520Same product: Apache Tomcat

Affected Assets

apache
tomcat
11.0.0 · 8.5.0 — 8.5.96 · 9.0.0 — 9.0.83 · 10.1.0 — 10.1.16

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V4.1.3
  • V4.2.4
  • V1.5.3
  • V4.1.1

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-01 mostly match
prevents

Configuration management can enforce uniform HTTP parsing rules across intermediaries, directly mitigating inconsistent interpretation.

DE.CM-01 partial match
prevents

Network monitoring can detect smuggling attempts via anomalous HTTP traffic or logs, while eliminating the inconsistency directly aids detection of such events.

PR.IR-01 partial match
prevents

Network protections can enforce consistent HTTP proxy/firewall behavior to block smuggling, and removing the weakness helps prevent unauthorized access via request smuggling.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing can detect HTTP request smuggling vulnerabilities in intermediary components.

A.8.20 Networks security partial match
degrades

Network security controls can enforce consistent HTTP parsing and proxy behavior that mitigates request smuggling.

A.8.21 Security of network services partial match
degrades

Secure network services include hardening proxies and gateways against inconsistent HTTP interpretation.

A.8.25 Secure development life cycle partial match
prevents

Secure SDLC practices require threat modeling and testing for HTTP parsing inconsistencies in intermediaries.

A.8.26 Application security requirements partial match
prevents

Application security requirements can mandate strict HTTP message validation and canonicalization.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles include consistent protocol handling and defense-in-depth for proxies.

References