CVE-2024-21733

Info Disclosure in Apache Tomcat 8.5.7 – 8.5.64

Public PoCInfo Disclosure

Published

19 January 2024

Modified

17 June 2026

Patch / advisory

View advisory

CVSS Score v3.1 5.3

Click a component to see what it means

Raw vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS Score 0.14 96th percentile

Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2024-21733 is a medium-severity Generation of Error Message Containing Sensitive Information (CWE-209) vulnerability in Apache Tomcat. Its CVSS base score is 5.3 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Software (T1592.002); ranked in the top 4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SI-11 (Error Handling) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

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

CVE-2024-21733 is a Generation of Error Message Containing Sensitive Information vulnerability, tracked as CWE-209, that affects Apache Tomcat versions 8.5.7 through 8.5.63 and 9.0.0-M11 through 9.0.43, with other end-of-life releases potentially impacted as well. The flaw carries a CVSS 3.1 score of 5.3 and permits partial disclosure of sensitive information over the network without authentication.

An unauthenticated remote attacker can trigger error responses that leak internal details, enabling information-gathering that supports further attacks against the Tomcat instance.

Apache Tomcat project advisories recommend upgrading to version 8.5.64 or later and 9.0.44 or later to resolve the issue; corresponding notices have been issued through the Apache mailing lists and downstream distributions such as Debian LTS.

The EPSS score has reached a peak of 0.7343 with a current value of 0.7095, indicating sustained but not sharply escalating exploitation interest since disclosure.

OWASP Top 10 for Web (2025)

EU & UK References

🇪🇺 ENISA EUVD: EUVD-2024-0340

Vulnerability Data

Generation of Error Message Containing Sensitive Information vulnerability in Apache Tomcat.This issue affects Apache Tomcat: from 8.5.7 through 8.5.63, from 9.0.0-M11 through 9.0.43. Other, EOL versions may also be affected. Users are recommended to upgrade to version 8.5.64 onwards or…

9.0.44 onwards, which contain a fix for the issue.

CWE(s): CWE-209

Related Threats

MITRE ATT&CK Enterprise Techniques

T1592.002 Software Reconnaissance

Adversaries may gather information about the victim's host software that can be used during targeting.

attack.mitre.org →

T1082 System Information Discovery Discovery

An adversary may attempt to get detailed information about the operating system and hardware, including version, patches, hotfixes, service packs, and architecture.

attack.mitre.org →

T1592 Gather Victim Host Information Reconnaissance

Adversaries may gather information about the victim's hosts that can be used during targeting.

attack.mitre.org →

T1595 Active Scanning Reconnaissance

Adversaries may execute active reconnaissance scans to gather information that can be used during targeting.

attack.mitre.org →

Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-29146Same product: Apache Tomcat

CVE-2026-42498Same product: Apache Tomcat

CVE-2026-66299Same product: Apache Tomcat

CVE-2024-23945Same vendor: Apache

CVE-2026-25854Same product: Apache Tomcat

CVE-2026-55955Same product: Apache Tomcat

CVE-2025-49125Same product: Apache Tomcat

CVE-2026-55956Same product: Apache Tomcat

CVE-2024-45384Same vendor: Apache

CVE-2026-34500Same product: Apache Tomcat

Affected Assets

apache

tomcat

9.0.0 · 8.5.7 — 8.5.64 · 9.0.1 — 9.0.44

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)

V16.5.1

Mitigating Controls (NIST 800-53 r5) AI

SI-11 Error Handling good match

si-11 directly requires error messages to avoid revealing exploitable information about the system or its data.

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-06 mostly match

prevents

Secure SDLC practices directly require sanitized error handling to prevent sensitive data disclosure.

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.8.28 Secure coding mostly match

prevents

Secure coding standards explicitly forbid exposing sensitive data in errors.

A.8.29 Security testing in development and acceptance mostly match

finds

Security testing can detect error messages that leak sensitive information.

A.8.15 Logging partial match

degrades

Logging policy can require suppression of sensitive data in error messages.

A.8.25 Secure development life cycle partial match

prevents

Secure SDLC mandates error-handling rules that avoid leaking sensitive information.