Bug 1915420 (CVE-2020-35653)

Summary:	CVE-2020-35653 python-pillow: Buffer over-read in PCX image reader
Product:	[Other] Security Response	Reporter:	Michael Kaplan <mkaplan>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	bdettelb, cstratak, manisandro, mcooper, miminar, python-maint, tomckay, torsava
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	python-pillow 8.1.0	Doc Type:	If docs needed, set a value
Doc Text:	A flaw was found in python-pillow. The PcxDecode in Pillow has a buffer over-read when decoding a crafted PCX file due to the user-supplied stride value trusted for buffer calculations. The highest threat from this vulnerability is to system availability.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-10-19 14:08:28 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:	1915421, 1915422, 1915428, 1916008
Bug Blocks:	1915433

Description Michael Kaplan 2021-01-12 16:03:05 UTC

In Pillow before 8.1.0, PcxDecode has a buffer over-read when decoding a crafted PCX file because the user-supplied stride value is trusted for buffer calculations.

External References: 

https://pillow.readthedocs.io/en/stable/releasenotes/8.1.0.html#security

Comment 1 Michael Kaplan 2021-01-12 16:03:29 UTC

Created python-pillow tracking bugs for this issue:

Affects: fedora-32 [bug 1915421]

Comment 3 Michael Kaplan 2021-01-12 16:08:16 UTC

Created python-pillow tracking bugs for this issue:

Affects: fedora-33 [bug 1915428]

Comment 4 Todd Cullum 2021-01-13 21:50:38 UTC

Upstream patch: https://github.com/python-pillow/Pillow/commit/2f409261eb1228e166868f8f0b5da5cda52e55bf .

Note that this patch says that it is for CVE-2020-35655 but the issue correponds to the upstream advisory and MITRE CVE for CVE-2020-35653[1][2].

1. https://pillow.readthedocs.io/en/stable/releasenotes/8.1.0.html#security
2. https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-35653

Comment 6 Todd Cullum 2021-01-13 23:16:17 UTC

Flaw summary:

In src/PIL/PcxImagePlugin.py PcxImageFile's _open() method accepted a `stride` length via `stride = i16(s, 66)` where `s` points to user-controlled input data from a PCX file. This meant that an attacker who is able to provide a crafted file with an invalid stride length could cause an out-of-bounds read that could potentially lead to an impact to application availability, or less likely, an impact to data confidentiality depending on how pillow is used in the application.

Comment 8 Mark Cooper 2021-01-29 01:52:06 UTC

The following Quay containers contain python-pillow 7.2.0 and hence are affected by the CVE (checked upstream 7.2.0 contains the same vulnerable code):
 - quay-registry-container
 - quay-builder-qemu-rhcos-container

Comment 11 errata-xmlrpc 2021-10-19 12:10:29 UTC

This issue has been addressed in the following products:

  Red Hat Quay 3

Via RHSA-2021:3917 https://access.redhat.com/errata/RHSA-2021:3917

Comment 12 Product Security DevOps Team 2021-10-19 14:08:28 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-2020-35653

Comment 13 errata-xmlrpc 2021-11-09 17:24:14 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2021:4149 https://access.redhat.com/errata/RHSA-2021:4149