Bug 2127010 (CVE-2022-3219)

Summary:	CVE-2022-3219 gnupg: denial of service issue (resource consumption) using compressed packets
Product:	[Other] Security Response	Reporter:	Sandipan Roy <saroy>
Component:	vulnerability	Assignee:	Nobody <nobody>
Status:	NEW ---	QA Contact:
Severity:	low	Docs Contact:
Priority:	low
Version:	unspecified	CC:	bcl, crypto-team, jjelen, kyoshida, rdieter, tm
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:	A vulnerability was found in GnuPG. GnuPG can spin on a relatively small input by crafting a public key with thousands of signatures attached and compressed down to a few kilobytes. This issue can potentially cause a denial of service.	Story Points:	---
Clone Of:		Environment:
Last Closed:		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:	2127012, 2127013, 2127014, 2127015, 2127016
Bug Blocks:	2112120

Description Sandipan Roy 2022-09-15 05:01:02 UTC

GnuPG can be made to spin on a relatively small input by (for example) crafting a public key with thousands of signatures attached, compressed down to just a few KB; see $URL and the surrounding email threads for more details and test-cases.

The reporter has some proposed patches at https://dev.gnupg.org/D556 (and in oss-security / gnupg-devel threads); mostly these flag/reject compressed packets and indeterminate-length packets in contexts where they make no sense and arguably are not within the spec (certificates, keys, detached signatures).

Comment 1 Sandipan Roy 2022-09-15 05:22:12 UTC

Created gnupg1 tracking bugs for this issue:

Affects: epel-all [bug 2127013]
Affects: fedora-all [bug 2127014]


Created gnupg2 tracking bugs for this issue:

Affects: fedora-all [bug 2127015]

Comment 3 Jakub Jelen 2022-09-19 10:31:13 UTC

The upstream bug [0] with discussion from May (!) says the upstream is not going to implement/merge this change. From what I read on the oss-security [1], there is a reproducer and claims of DoS attacks. My reading is that this is not infinite recursion, but only slow processing of malformed inputs, which I consider low priority right now.

[1] https://dev.gnupg.org/T5993
[1] https://marc.info/?l=oss-security&m=165696590211434&w=4

Comment 4 Brian Lane 2022-09-19 15:36:27 UTC

(In reply to Jakub Jelen from comment #3)
> The upstream bug [0] with discussion from May (!) says the upstream is not
> going to implement/merge this change. From what I read on the oss-security
> [1], there is a reproducer and claims of DoS attacks. My reading is that
> this is not infinite recursion, but only slow processing of malformed
> inputs, which I consider low priority right now.
> 
> [1] https://dev.gnupg.org/T5993
> [1] https://marc.info/?l=oss-security&m=165696590211434&w=4

I agree. I am reluctant to backport things that upstream hasn't committed to fixing/changing and won't be doing anything for this on gpg1 until there is upstream consensus.