Internet Bug Bounty: mod_userdir CRLF injection (CVE-2016-4975)

2018-09-1322:13:05

bobrov

hackerone.com

$500

354

6.1 Medium

CVSS3

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

REQUIRED

Scope

CHANGED

Confidentiality Impact

LOW

Integrity Impact

LOW

Availability Impact

NONE

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

4.3 Medium

CVSS2

Access Vector

NETWORK

Access Complexity

MEDIUM

Authentication

NONE

Confidentiality Impact

NONE

Integrity Impact

PARTIAL

Availability Impact

NONE

AV:N/AC:M/Au:N/C:N/I:P/A:N

0.004 Low

EPSS

Percentile

68.4%

JSON

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.

Reported to security team 24th July 2016
Issue public 14th August 2018
Update Released 20th December 2016
Affects 2.4.23, 2.4.20, 2.4.18, 2.4.17, 2.4.16, 2.4.12, 2.4.10, 2.4.9, 2.4.7, 2.4.6, 2.4.4, 2.4.3, 2.4.2, 2.4.1

https://httpd.apache.org/security/vulnerabilities_24.html#CVE-2016-4975
https://httpd.apache.org/security/vulnerabilities_22.html#CVE-2016-4975