Bug 1463205 (CVE-2017-7668) - CVE-2017-7668 httpd: ap_find_token() buffer overread
Summary: CVE-2017-7668 httpd: ap_find_token() buffer overread
Keywords:
Status: CLOSED ERRATA
Alias: CVE-2017-7668
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
URL:
Whiteboard:
Depends On: 1463208 1464876 1464877 1465916 1466263 1466264 1473691 1473692 1473693 1510060 1510061
Blocks: 1463212 1464082
TreeView+ depends on / blocked
 
Reported: 2017-06-20 11:29 UTC by Andrej Nemec
Modified: 2021-06-10 12:28 UTC (History)
44 users (show)

Fixed In Version: httpd 2.2.34, httpd 2.4.26
Doc Type: If docs needed, set a value
Doc Text:
A buffer over-read flaw was found in the httpd's ap_find_token() function. A remote attacker could use this flaw to cause httpd child process to crash via a specially crafted HTTP request.
Clone Of:
Environment:
Last Closed: 2019-06-08 03:15:20 UTC
Embargoed:

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHSA-2017:2479 0 normal SHIPPED_LIVE Important: httpd security update 2017-08-15 22:23:44 UTC
Red Hat Product Errata RHSA-2017:2483 0 normal SHIPPED_LIVE Important: httpd24-httpd security update 2017-08-17 03:04:17 UTC
Red Hat Product Errata RHSA-2017:3193 0 normal SHIPPED_LIVE Important: httpd security update 2017-11-13 22:35:40 UTC
Red Hat Product Errata RHSA-2017:3194 0 normal SHIPPED_LIVE Important: httpd security update 2017-11-13 22:36:28 UTC

Description Andrej Nemec 2017-06-20 11:29:23 UTC 
The HTTP strict parsing changes added in 2.2.32 and 2.4.24 introduced a bug in token list parsing, which allows ap_find_token() to search past the end of its input string. By maliciously crafting a sequence of request headers, an attacker may be able to cause a segmentation fault, or to force ap_find_token() to return an incorrect value.

External References:

https://httpd.apache.org/security/vulnerabilities_24.html
https://httpd.apache.org/security/vulnerabilities_22.html
Comment 1 Andrej Nemec 2017-06-20 11:38:04 UTC 
Created httpd tracking bugs for this issue:

Affects: fedora-all [bug 1463208]
Comment 2 Tomas Hoger 2017-06-22 11:56:36 UTC 
Upstream commit:

2.4: https://github.com/apache/httpd/commit/a585e36e06a53170be6d2d462ceb5b30b8382988
2.2: https://github.com/apache/httpd/commit/ad581ced12363ce82ffcb16133f236b2e31563e1
Comment 6 Tomas Hoger 2017-06-26 20:45:00 UTC 
(In reply to Andrej Nemec from comment #0)
> The HTTP strict parsing changes added in 2.2.32 and 2.4.24 introduced a bug
> in token list parsing, which allows ap_find_token() to search past the end
> of its input string.

The strict HTTP parsing was a fix for flaw with CVE id CVE-2016-8743 and is tracked via bug 1406822.  The change was already backported to multiple Red Hat products, even if they contain older httpd version.
Comment 15 errata-xmlrpc 2017-08-15 18:26:21 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2017:2479 https://access.redhat.com/errata/RHSA-2017:2479
Comment 16 errata-xmlrpc 2017-08-16 23:07:09 UTC 
This issue has been addressed in the following products:

  Red Hat Software Collections for Red Hat Enterprise Linux 7
  Red Hat Software Collections for Red Hat Enterprise Linux 6
  Red Hat Software Collections for Red Hat Enterprise Linux 6.7 EUS
  Red Hat Software Collections for Red Hat Enterprise Linux 7.3 EUS

Via RHSA-2017:2483 https://access.redhat.com/errata/RHSA-2017:2483
Comment 18 errata-xmlrpc 2017-11-13 17:37:11 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7.2 Extended Update Support

Via RHSA-2017:3193 https://access.redhat.com/errata/RHSA-2017:3193
Comment 19 errata-xmlrpc 2017-11-13 17:41:06 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7.3 Extended Update Support

Via RHSA-2017:3194 https://access.redhat.com/errata/RHSA-2017:3194
Note You need to log in before you can comment on or make changes to this bug.