CVE-2016-4975 - CVE House
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Status published Medium CVE-2016-4975

mod_userdir CRLF injection

Vulnerability Description

Possible CRLF injection allowing HTTP response splitting attacks for sites which use mod_userdir. This issue was mitigated by changes made in 2.4.25 and 2.2.32 which prohibit CR or LF injection into the "Location" or other outbound header key or value. Fixed in Apache HTTP Server 2.4.25 (Affected 2.4.1-2.4.23). Fixed in Apache HTTP Server 2.2.32 (Affected 2.2.0-2.2.31).

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • The issue was discovered by Sergey Bobrov

References

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Affected Vendor

Apache Software Foundation

View all reports →

Affected Software

Apache HTTP Server
Vulnerable Versions:
Fixed in Apache HTTP Server 2.4.25 (Affected 2.4.1-2.4.23), Fixed in Apache HTTP Server 2.2.32 (Affected 2.2.0-2.2.31)

Timeline

Official Publish: August 14th, 2018
Last Modified: September 16th, 2024
Added to House: July 20th, 2026

CVSS Vectors

V3: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.