Bug 1852814 (CVE-2020-11538)

Summary:	CVE-2020-11538 python-pillow: out-of-bounds reads/writes in the parsing of SGI image files in expandrow/expandrow2
Product:	[Other] Security Response	Reporter:	Marian Rehak <mrehak>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	bdettelb, cstratak, jschorr, manisandro, miminar, python-maint, tomckay, torsava, tsmetana
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	python-pillow 7.1.0	Doc Type:	If docs needed, set a value
Doc Text:	An out-of-bounds read/write flaw was found in python-pillow, in the way SGI RLE images are decoded. An application that uses python-pillow to decode untrusted images may be vulnerable. This flaw allows an attacker to crash the application or potentially execute code on the system. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2020-07-28 19:28:34 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:	1852815, 1852816, 1854807, 1854808, 1854809, 1854810
Bug Blocks:	1852831

Description Marian Rehak 2020-07-01 11:16:36 UTC

In libImaging/SgiRleDecode.c in Pillow through 7.0.0, a number of out-of-bounds reads/writes exist in the parsing of SGI image files, a different issue than CVE-2020-5311.

Pull Request:

https://github.com/python-pillow/Pillow/pull/4538

Upstream Advisory:

https://pillow.readthedocs.io/en/stable/releasenotes/7.1.0.html

Comment 1 Marian Rehak 2020-07-01 11:17:23 UTC

Created python-pillow tracking bugs for this issue:

Affects: fedora-31 [bug 1852815]
Affects: fedora-32 [bug 1852816]

Comment 3 Jason Shepherd 2020-07-02 01:32:32 UTC

Upstream commit:
https://github.com/python-pillow/Pillow/commit/2ef59fdbaeb756bc512ab3f2ad15ac45665b303d

Comment 4 Riccardo Schirone 2020-07-08 08:57:47 UTC

Statement:

This issue did not affect the versions of python-pillow and python-imaging as shipped with Red Hat Enterprise Linux 5, 6, and 7 as they did not include the SGI RLE image decoder, where the flaw lies.

Comment 5 Riccardo Schirone 2020-07-08 09:02:33 UTC

Valgrind report:
```
==10235== Invalid write of size 2                                                              
==10235==    at 0x82BBAD0: expandrow2 (SgiRleDecode.c:87)
==10235==    by 0x82BBAD0: ImagingSgiRleDecode (SgiRleDecode.c:176)
==10235==    by 0x8294057: _decode (decode.c:130)            
==10235==    by 0x5488431: _PyCFunction_FastCallDict (in /usr/lib64/libpython3.6m.so.1.0)
==10235==    by 0x5488A4F: ??? (in /usr/lib64/libpython3.6m.so.1.0)   
==10235==    by 0x54B14C3: _PyEval_EvalFrameDefault (in /usr/lib64/libpython3.6m.so.1.0)
==10235==    by 0x5463A39: ??? (in /usr/lib64/libpython3.6m.so.1.0)  
==10235==    by 0x5488B35: ??? (in /usr/lib64/libpython3.6m.so.1.0)      
==10235==    by 0x54B14C3: _PyEval_EvalFrameDefault (in /usr/lib64/libpython3.6m.so.1.0)
==10235==    by 0x5493396: PyEval_EvalCodeEx (in /usr/lib64/libpython3.6m.so.1.0)
==10235==    by 0x54940EA: PyEval_EvalCode (in /usr/lib64/libpython3.6m.so.1.0)
==10235==    by 0x5533961: ??? (in /usr/lib64/libpython3.6m.so.1.0)
==10235==    by 0x540B632: PyRun_FileExFlags (in /usr/lib64/libpython3.6m.so.1.0)
==10235==  Address 0xbee2f80 is 0 bytes after a block of size 3,840 alloc'd
==10235==    at 0x4C331EA: calloc (vg_replace_malloc.c:762)
==10235==    by 0x82BB8D1: ImagingSgiRleDecode (SgiRleDecode.c:138)
==10235==    by 0x8294057: _decode (decode.c:130)
==10235==    by 0x5488431: _PyCFunction_FastCallDict (in /usr/lib64/libpython3.6m.so.1.0)
==10235==    by 0x5488A4F: ??? (in /usr/lib64/libpython3.6m.so.1.0)
==10235==    by 0x54B14C3: _PyEval_EvalFrameDefault (in /usr/lib64/libpython3.6m.so.1.0)
==10235==    by 0x5463A39: ??? (in /usr/lib64/libpython3.6m.so.1.0)
==10235==    by 0x5488B35: ??? (in /usr/lib64/libpython3.6m.so.1.0)
==10235==    by 0x54B14C3: _PyEval_EvalFrameDefault (in /usr/lib64/libpython3.6m.so.1.0)
==10235==    by 0x5493396: PyEval_EvalCodeEx (in /usr/lib64/libpython3.6m.so.1.0)
==10235==    by 0x54940EA: PyEval_EvalCode (in /usr/lib64/libpython3.6m.so.1.0)
==10235==    by 0x5533961: ??? (in /usr/lib64/libpython3.6m.so.1.0)
==10235== 
```

Comment 6 Riccardo Schirone 2020-07-08 09:03:41 UTC

An heap-based out-of-bounds read/write is present in function expandrow2() as called by ImagingSgiRleDecode.

Comment 9 errata-xmlrpc 2020-07-28 13:37:34 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2020:3185 https://access.redhat.com/errata/RHSA-2020:3185

Comment 10 Product Security DevOps Team 2020-07-28 19:28:34 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-2020-11538

Comment 11 errata-xmlrpc 2020-08-04 07:39:38 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.1 Extended Update Support

Via RHSA-2020:3299 https://access.redhat.com/errata/RHSA-2020:3299

Comment 12 errata-xmlrpc 2020-08-04 10:28:01 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.0 Update Services for SAP Solutions

Via RHSA-2020:3302 https://access.redhat.com/errata/RHSA-2020:3302

Comment 13 Mark Cooper 2021-02-04 00:59:56 UTC

Set Quay affects to Low to match CVE-2020-10379 and given:

While python-pillow is listed as a dependency of Red Hat Quay, it is not used by the application.

Comment 14 errata-xmlrpc 2021-02-04 16:14:37 UTC

This issue has been addressed in the following products:

  Red Hat Quay 3

Via RHSA-2021:0420 https://access.redhat.com/errata/RHSA-2021:0420