CVE-2026-79768
Description
A flaw was found in Apache HTTP Server's mod_userdir module. When configured with an absolute path without wildcards for the UserDir directive, the server fails to properly resolve single-dot directory ('/./') path equivalence. A remote attacker can exploit this issue by submitting a crafted HTTP request, potentially bypassing path restrictions to access unauthorized files, leading to information disclosure.
Mitigation
Disable user directories or avoid configuring absolute directory paths without wildcards in the `UserDir` directive.
1. If per-user web directories are not required, ensure `UserDir disabled` is configured in `/etc/httpd/conf.d/userdir.conf`, or comment out the module loading directive:
# LoadModule userdir_module modules/mod_userdir.so
2. If user directories are necessary, configure `UserDir` using a relative path (for example, `UserDir public_html`) rather than an absolute path.
3. Reload the Apache HTTP Server configuration to apply changes:
systemctl reload httpd
Caveats: Disabling mod_userdir prevents users from publishing content via `~username` URLs. Reloading the httpd service may briefly affect active HTTP connections.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.3 | N/A | 5.3 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | Low | N/A | Low |
| Integrity Impact | None | N/A | None |
| Availability Impact | None | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Understanding the Weakness (CWE)
Confidentiality,Integrity,Access Control
Technical Impact: Read Files or Directories; Modify Files or Directories; Bypass Protection Mechanism
An attacker may be able to traverse the file system to unintended locations and read or overwrite the contents of unexpected files. If the files are used for a security mechanism than an attacker may be able to bypass the mechanism.
Frequently Asked Questions
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