CVE-2026-44186
Description
A flaw was found in the mod_proxy_ftp module of the Apache HTTP Server. A remote attacker, by controlling a backend File Transfer Protocol (FTP) server, can trigger an infinite loop. This vulnerability, categorized as a Loop with Unreachable Exit Condition, leads to a Denial of Service (DoS) for the affected server.
Statement
A loop with an unreachable exit condition flaw was found in the mod_proxy_ftp module of the Apache HTTP Server. A remote attacker could exploit this vulnerability by tricking the server into connecting to a malicious or compromised backend FTP server, causing the proxy_ftp_handler component to enter an infinite loop. This results in CPU exhaustion and a denial of service (DoS) condition on the affected system.
Mitigation
To mitigate this issue, you can disable the `mod_proxy_ftp` module if your environment does not require it.
#### **Step 1: Disable the Module**
Open your Apache HTTP Server configuration file (commonly located at `/etc/httpd/conf.modules.d/00-proxy.conf` or `/etc/httpd/conf/httpd.conf`) and comment out or remove the following line:
# LoadModule proxy_ftp_module modules/mod_proxy_ftp.so#### **Step 2: Restart the Service**
Restart the `httpd` service to apply the configuration changes:
systemctl restart httpd**Note:** Disabling this module may impact applications or services that rely on Apache's FTP proxy functionality.
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 | 7.3 | N/A | 7.3 |
| 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 | Low | N/A | Low |
| Availability Impact | Low | N/A | Low |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Amplification
An infinite loop will cause unexpected consumption of resources, such as CPU cycles or memory. The software's operation may slow down, or cause a long time to respond.
Frequently Asked Questions
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