CVE-2024-47252

Apache HTTP Server: mod_ssl error log variable escaping

Published Jul 10, 2025 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Description
Insufficient escaping of user-supplied data in mod_ssl in Apache HTTP Server 2.4.63 and earlier allows an untrusted SSL/TLS client to insert escape characters into log files in some configurations.

In a logging configuration where CustomLog is used with "%{varname}x" or "%{varname}c" to log variables provided by mod_ssl such as SSL_TLS_SNI, no escaping is performed by either mod_log_config or mod_ssl and unsanitized data provided by the client may appear in log files.

Remediation

No solution or workaround provided in the CVE record

Tracking

Sign in to view the affected projects.

Advisories

Source ID Title
Debian DLA Debian DLA DLA-4270-1 apache2 security update
EUVD EUVD EUVD-2024-54773 Insufficient escaping of user-supplied data in mod_ssl in Apache HTTP Server 2.4.63 and earlier allows an untrusted SSL/TLS client to insert escape characters into log files in some configurations. In a logging configuration where CustomLog is used with "%{varname}x" or "%{varname}c" to log variables provided by mod_ssl such as SSL_TLS_SNI, no escaping is performed by either mod_log_config or mod_ssl and unsanitized data provided by the client may appear in log files.
Ubuntu USN Ubuntu USN USN-7639-1 Apache HTTP Server vulnerabilities
Ubuntu USN Ubuntu USN USN-7639-2 Apache HTTP Server vulnerabilities
Ubuntu USN Ubuntu USN USN-8338-1 Apache HTTP Server vulnerabilities
History
Type Values Removed Values Added
First Time appeared Apache http Server
CPEs cpe:2.3:a:apache:http_server:*:*:*:*:*:*:*:*
Vendors & Products Apache http Server
Type Values Removed Values Added
Metrics epss

{'score': 0.00018}

epss

{'score': 0.00041}

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N'}

Type Values Removed Values Added
Weaknesses CWE-117
References
Metrics threat_severity

None

cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N'}

threat_severity

Moderate

Type Values Removed Values Added
Metrics epss

{'score': 0.00018}

Type Values Removed Values Added
Description Insufficient escaping of user-supplied data in mod_ssl in Apache HTTP Server 2.4.63 and earlier allows an untrusted SSL/TLS client to insert escape characters into log files in some configurations. In a logging configuration where CustomLog is used with "%{varname}x" or "%{varname}c" to log variables provided by mod_ssl such as SSL_TLS_SNI, no escaping is performed by either mod_log_config or mod_ssl and unsanitized data provided by the client may appear in log files.
Title Apache HTTP Server: mod_ssl error log variable escaping
Weaknesses CWE-150
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
apache
Published
Updated
Nov 4, 2025, 9:08 PM
Reserved
Sep 23, 2024, 3:25 PM
Status
Modified
Published
Jul 10, 2025, 5:15 PM
Modified
Jun 17, 2026, 7:56 AM
Severity
Moderate
Public date
Jul 14, 2025, 7:17 AM