CVE-2021-42013
Apache HTTP Server contains a path traversal vulnerability that allows an attacker to perform remote code execution if files outside directories…
Browse: All 2021 CVEs · All vendors
- CISA KEV
- Yes — actively exploited (added 2021-11-03, remediation due 2021-11-17)
- Ransomware
- Known ransomware campaign use
- Weakness (CWE)
- CWE-22
Description
Apache HTTP Server contains a path traversal vulnerability that allows an attacker to perform remote code execution if files outside directories configured by Alias-like directives are not under default require all denied or if CGI scripts are enabled. This CVE ID resolves an incomplete patch for CVE-2021-41773.
Affected products
- Apache HTTP Server
Affected ranges per NVD CPE data; confirm exact versions in the vendor advisory.
Required action (CISA)
Apply updates per vendor instructions. Federal remediation deadline: 2021-11-17.
How to prioritize this
This vulnerability is on the CISA KEV list, meaning it is being actively exploited — treat it as urgent regardless of the raw CVSS number. Use the live CVE lookup for the latest NVD data, and the CVSS 3.1 calculator to model your own environmental score.
FAQ
Is CVE-2021-42013 actively exploited?
Yes. CISA added CVE-2021-42013 to its Known Exploited Vulnerabilities (KEV) catalog on 2021-11-03, with a federal remediation deadline of 2021-11-17. A KEV listing means real-world exploitation is confirmed, so patching this should be prioritized above many higher-CVSS bugs that aren't being exploited.
What is the CVSS score of CVE-2021-42013?
CVE-2021-42013 has no published CVSS base score yet — NVD analysis can lag disclosure. Check the vendor references for an interim severity.
Related vulnerabilities
- CVE-2024-38475 — Apache HTTP Server
- CVE-2021-41773 — Apache HTTP Server
- CVE-2019-0211 — Apache HTTP Server
- CVE-2026-34486 — Apache Tomcat
- CVE-2026-34197 — Apache ActiveMQ
- CVE-2025-24813 — Apache Tomcat
Data source: NVD & CISA KEV. Shown as-is; nothing added. Last generated from NVD data — re-check the live tool for updates.
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