CVE-2026-56153
Description
A flaw was found in httpd's mod_charset_lite module. A heap-based buffer overflow (an out-of-bounds memory write) occurs in the finish_partial_char function when handling character set conversions. A remote attacker can exploit this flaw by sending specially crafted requests, leading to memory corruption. This issue primarily results in a Denial of Service (DoS) condition by crashing the server process.
Mitigation
Disable the mod_charset_lite module if character set translation is not required.
1. Locate the configuration file loading the module, typically within `/etc/httpd/conf.modules.d/` (such as `00-base.conf` or a dedicated module configuration file).
2. Comment out or remove the `LoadModule charset_lite_module` line:
# LoadModule charset_lite_module modules/mod_charset_lite.so3. Reload the httpd service to apply the configuration change:
systemctl reload httpd
Caveats: Applications that depend on mod_charset_lite for on-the-fly character set conversion will fail to translate character sets once the module is disabled.
Warning: Reloading or restarting the httpd service will momentarily disrupt active network connections or in-flight requests.
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 | 7.5 | N/A | 7.5 |
| 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 | None | N/A | High |
| Integrity Impact | None | N/A | None |
| Availability Impact | High | N/A | None |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Memory; Execute Unauthorized Code or Commands
Write operations could cause memory corruption. In some cases, an adversary can modify control data such as return addresses in order to execute unexpected code.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
Attempting to access out-of-range, invalid, or unauthorized memory could cause the product to crash.
Other
Technical Impact: Unexpected State
Subsequent write operations can produce undefined or unexpected results.
Frequently Asked Questions
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