Rapid7 Vulnerability & Exploit Database

Apache HTTPD: Out of bound write in mod_authnz_ldap when using too small Accept-Language values (CVE-2017-15710)

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Apache HTTPD: Out of bound write in mod_authnz_ldap when using too small Accept-Language values (CVE-2017-15710)

Severity
5
CVSS
(AV:N/AC:L/Au:N/C:N/I:N/A:P)
Published
03/26/2018
Created
07/25/2018
Added
03/26/2018
Modified
01/30/2020

Description

The affected asset is vulnerable to this vulnerability ONLY if it is running one of the following modules: mod_authnz_ldap. Review your web server configuration for validation. mod_authnz_ldap, if configured with AuthLDAPCharsetConfig, uses the Accept-Language header value to lookup the right charset encoding when verifying the user's credentials. If the header value is not present in the charset conversion table, a fallback mechanism is used to truncate it to a two characters value to allow a quick retry (for example, 'en-US' is truncated to 'en'). A header value of less than two characters forces an out of bound write of one NUL byte to a memory location that is not part of the string. In the worst case, quite unlikely, the process would crash which could be used as a Denial of Service attack. In the more likely case, this memory is already reserved for future use and the issue has no effect at all.

Solution(s)

  • apache-httpd-upgrade-2_4_33

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