Bug 1850579 (CVE-2020-12862)

Summary: CVE-2020-12862 sane-backends: Out-of-bounds read in decode_binary
Product: [Other] Security Response Reporter: Pedro Sampaio <psampaio>
Component: vulnerabilityAssignee: Nobody <nobody>
Status: NEW --- QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: mike, nphilipp, thibault.north, zdohnal
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: sane-backends 1.0.30 Doc Type: If docs needed, set a value
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Clone Of: Environment:
Last Closed: Type: ---
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 1850580, 1850582, 1852676    
Bug Blocks: 1848100    

Description Pedro Sampaio 2020-06-24 13:52:16 UTC
A flaw was found in sane-backends before version 1.0.30. An out-of-bounds read in decode_binary may lead to disclosure of information.

Upstream issue:

https://gitlab.com/sane-project/backends/-/issues/279#issue-5-ghsl-2020-082-out-of-bounds-read-in-decode_binary

References:

https://gitlab.com/sane-project/backends/-/releases

Comment 1 Pedro Sampaio 2020-06-24 13:53:32 UTC
Created mingw-sane-backends tracking bugs for this issue:

Affects: fedora-all [bug 1850582]


Created sane-backends tracking bugs for this issue:

Affects: fedora-all [bug 1850580]

Comment 3 Huzaifa S. Sidhpurwala 2020-07-01 04:36:59 UTC
Statement:

The vulnerable code is a part of "driver for Epson ESC/I-2 scanners" which was first introduced in sane-backends-1.0.25. (via https://gitlab.com/sane-project/backends/-/commit/d72f4663c0ad6e6f779c15c8baf5f92b675ae19a)  Therefore only versions of sane-backends shipped with Red Hat Enterprise Linux 8 is affected by this flaw.

Comment 5 Huzaifa S. Sidhpurwala 2020-07-01 04:43:40 UTC
Mitigation:

This flaw can be mitigated by limiting network scanner discovery to a trusted subnet via the "net" configuration in the "/etc/sane.d/epsonds.conf" configuration file. Also automatic network scanner discovery can be turned off by commenting out the line "net autodiscovery" in the same configuration file.

Comment 6 Huzaifa S. Sidhpurwala 2020-07-01 05:08:26 UTC
Upstream patch: https://gitlab.com/sane-project/backends/-/commit/3d005c2570a71fe93a63192d9c47ee54cb39049b