Apache HTTP Server 2.4.49 Path Traversal and RCE
Actively exploited in the wild. Patch or mitigate immediately — don't wait for a maintenance window.
An unauthenticated attacker, remotely over the network, with no user interaction, can fully compromise the system — steal data, tamper with it and take it offline.
A flaw was found in a change made to path normalization in Apache HTTP Server 2.4.49. An attacker could use a path traversal attack to map URLs to files outside the directories configured by Alias-like directives. If files outside of these directories are not protected by the usual default configuration "require all denied", these requests can succeed. If CGI scripts are also enabled for these aliased pathes, this could allow for remote code execution. This issue is known to be exploited in the wild. This issue only affects Apache 2.4.49 and not earlier versions. The fix in Apache HTTP Server 2.4.50 was found to be incomplete, see CVE-2021-42013.
Techniques marked “observed” are corroborated by threat intelligence; the rest are inferred from the weakness type (CWE) and attack vector.
Corroborated threat activity referencing this CVE — with source and confidence, not inference.
These techniques were analysed against this CVE's real-world exploitation — the matching entries in the ATT&CK chain above are marked “observed”.
Generated by Wavense from the CVE record — an immediate mitigation and the permanent fix.
Immediately restrict access to all directories outside of explicitly served web content using 'require all denied' directives in Apache configurations. Disable CGI script execution on all aliased directories, especially for non-critical paths, until a patch can be applied. Monitor Apache access logs for unusual path requests or attempts to access restricted files to detect exploitation attempts.
The permanent resolution is to upgrade Apache HTTP Server to version 2.4.51 or later. This vulnerability specifically affects Apache 2.4.49, and the fix in 2.4.50 was found to be incomplete, leading to a related vulnerability (CVE-2021-42013). Immediately apply the latest stable Apache updates to fully remediate this issue and ensure protection against subsequent related vulnerabilities.
An attacker can exploit this flaw to traverse directories outside the intended web root, potentially accessing sensitive files and configurations. If CGI scripts are enabled on aliased paths, this vulnerability can lead to remote code execution, giving the attacker full control over the compromised server. This critical issue has been actively exploited in the wild, posing severe data breach and system compromise risks.
Other CVEs affecting http server
Vulnerability in the Oracle HTTP Server, Oracle Weblogic Server Proxy Plug-in product of Oracle Fusion Middleware (component: Weblogic Server Proxy Plug-in for Apache HTTP Server, Weblogic Server Proxy Plug-in for IIS). Supported versions that are affected are 12.2.1.4.0, 14.1.1.0.0 and 14.1.2.0.0. Easily exploitable vulnerability allows unauthenticated attacker with network access via HTTP to compromise Oracle HTTP Server, Oracle Weblogic Server Proxy Plug-in. While the vulnerability is in Oracle HTTP Server, Oracle Weblogic Server Proxy Plug-in, attacks may significantly impact additional products (scope change). Successful attacks of this vulnerability can result in unauthorized creation, deletion or modification access to critical data or all Oracle HTTP Server, Oracle Weblogic Server Proxy Plug-in accessible data as well as unauthorized access to critical data or complete access to all Oracle HTTP Server, Oracle Weblogic Server Proxy Plug-in accessible data. Note: Affected version for Weblogic Server Proxy Plug-in for IIS is 12.2.1.4.0 only. CVSS 3.1 Base Score 10.0 (Confidentiality and Integrity impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N).
The mod_copy module in ProFTPD 1.3.5 allows remote attackers to read and write to arbitrary files via the site cpfr and site cpto commands.
In PHP versions 8.1.* before 8.1.29, 8.2.* before 8.2.20, 8.3.* before 8.3.8, when using Apache and PHP-CGI on Windows, if the system is set up to use certain code pages, Windows may use "Best-Fit" behavior to replace characters in command line given to Win32 API functions. PHP CGI module may misinterpret those characters as PHP options, which may allow a malicious user to pass options to PHP binary being run, and thus reveal the source code of scripts, run arbitrary PHP code on the server, etc.
Roundcube before 1.3.17 and 1.4.x before 1.4.12 is prone to a potential SQL injection via search or search_params.
It was found that the fix for CVE-2021-41773 in Apache HTTP Server 2.4.50 was insufficient. An attacker could use a path traversal attack to map URLs to files outside the directories configured by Alias-like directives. If files outside of these directories are not protected by the usual default configuration "require all denied", these requests can succeed. If CGI scripts are also enabled for these aliased pathes, this could allow for remote code execution. This issue only affects Apache 2.4.49 and Apache 2.4.50 and not earlier versions.
Grafana is an open source data visualization platform. In affected versions unauthenticated and authenticated users are able to view the snapshot with the lowest database key by accessing the literal paths: /dashboard/snapshot/:key, or /api/snapshots/:key. If the snapshot "public_mode" configuration setting is set to true (vs default of false), unauthenticated users are able to delete the snapshot with the lowest database key by accessing the literal path: /api/snapshots-delete/:deleteKey. Regardless of the snapshot "public_mode" setting, authenticated users are able to delete the snapshot with the lowest database key by accessing the literal paths: /api/snapshots/:key, or /api/snapshots-delete/:deleteKey. The combination of deletion and viewing enables a complete walk through all snapshot data while resulting in complete snapshot data loss. This issue has been resolved in versions 8.1.6 and 7.5.11. If for some reason you cannot upgrade you can use a reverse proxy or similar to block access to the literal paths: /api/snapshots/:key, /api/snapshots-delete/:deleteKey, /dashboard/snapshot/:key, and /api/snapshots/:key. They have no normal function and can be disabled without side effects.
A logic issue was addressed with improved restrictions. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, iOS 14.4 and iPadOS 14.4. A remote attacker may be able to cause arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited..
A logic issue was addressed with improved restrictions. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, iOS 14.4 and iPadOS 14.4. A remote attacker may be able to cause arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited..