What’s Vulnerable › Vulnerabilities

CVE-2023-24021

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.9% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2023-01-20 · updated 2026-06-17
• Weakness: CWE-170

Description

Incorrect handling of '\0' bytes in file uploads in ModSecurity before 2.9.7 may allow for Web Application Firewall bypasses and buffer over-reads on the Web Application Firewall when executing rules that read the FILES_TMP_CONTENT collection.

Affected products

• Debian Linux: 10.0
• Trustwave Modsecurity: before 2.9.7 — fixed in 2.9.7

How to fix

Upgrade to a fixed version: Trustwave Modsecurity 2.9.7. Check the vendor advisory for mitigations.

References

• https://github.com/SpiderLabs/ModSecurity/pull/2857
• https://github.com/SpiderLabs/ModSecurity/pull/2857/commits/4324f0ac59f8225aa44bc5034df60dbeccd1d334
• https://github.com/SpiderLabs/ModSecurity/releases/tag/v2.9.7
• https://lists.debian.org/debian-lts-announce/2023/01/msg00023.html
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/52TGCZCOHYBDCVWJYNN2PS4QLOHCXWTQ/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SYRTXTOQQI6SB2TLI5QXU76DURSLS4XI/
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WCH6JM4I4MD4YABYFHSBDDOUFDGIFJKL/
• https://github.com/SpiderLabs/ModSecurity/pull/2857
• https://github.com/SpiderLabs/ModSecurity/pull/2857/commits/4324f0ac59f8225aa44bc5034df60dbeccd1d334
• https://github.com/SpiderLabs/ModSecurity/releases/tag/v2.9.7
• https://lists.debian.org/debian-lts-announce/2023/01/msg00023.html
• https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/52TGCZCOHYBDCVWJYNN2PS4QLOHCXWTQ/

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