Bug 1837842 (CVE-2019-11048)

Summary: CVE-2019-11048 php: Integer wraparounds when receiving multipart forms
Product: [Other] Security Response Reporter: Marian Rehak <mrehak>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED ERRATA QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: aogburn, fedora, hhorak, jorton, kyoshida, nbhumkar, rcollet, security-response-team, webstack-team, yozone
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: php 7.3.18, php 7.2.31, php 7.4.6 Doc Type: If docs needed, set a value
Doc Text:
A flaw was found in PHP under a non-default configuration, where it was vulnerable to integer wraparounds during the reception of a multipart POST request. This flaw allows a remote attacker to repeatedly crash PHP and fill the filesystem with temporary PHP files, resulting in a denial of service.
Story Points: ---
Clone Of: Environment:
Last Closed: 2020-09-08 13:19:11 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 1837843, 1837913, 1837915, 1837916, 1837918, 1837919, 1837920, 1837921, 1837922, 1837923, 1837924, 1837925, 1838693    
Bug Blocks: 1837849    

Description Marian Rehak 2020-05-20 06:35:17 UTC
There are 2 integers wraparound flaws in php-src/main/rfc1867.c that allow a malicious user to crash PHP during a multipart/form-data file upload. A large multipart/form-data variable, or filename, may cause an integer overflow that leads to a subsequent crash.
Temporary files are not cleaned up, and could ultimately fill up the file system containing PHP temporary data.

Upstream Issues:

https://bugs.php.net/bug.php?id=78876
https://bugs.php.net/bug.php?id=78875

Comment 1 Marian Rehak 2020-05-20 06:35:36 UTC
Created php tracking bugs for this issue:

Affects: fedora-all [bug 1837843]

Comment 4 Joe Orton 2020-05-20 14:56:50 UTC
Note that this issue requires a pathological configuration to trigger; post_max_size must be set to 2GB or higher.  Such a configuration allows an effective Denial of Service attack against any server and should never be used in production.

Comment 5 Cedric Buissart 2020-05-21 13:03:18 UTC
Statement:

The severity of this issue is considered Moderate because it requires an unlikely large `post_max_size` to be configured.

Comment 6 Cedric Buissart 2020-05-21 13:03:21 UTC
Mitigation:

Ensure that `post_max_size` is set to a value less than 2GB, or remains default.

Comment 14 errata-xmlrpc 2020-09-08 09:47:30 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2020:3662 https://access.redhat.com/errata/RHSA-2020:3662

Comment 15 Product Security DevOps Team 2020-09-08 13:19:11 UTC
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):

https://access.redhat.com/security/cve/cve-2019-11048

Comment 16 errata-xmlrpc 2020-12-01 12:03:29 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 7.6 EUS
  Red Hat Software Collections for Red Hat Enterprise Linux 7.7 EUS

Via RHSA-2020:5275 https://access.redhat.com/errata/RHSA-2020:5275