Bug 1846026 (CVE-2020-10772)

Summary: CVE-2020-10772 unbound: incomplete fix for CVE-2020-12662 in RHEL7
Product: [Other] Security Response Reporter: Riccardo Schirone <rschiron>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED ERRATA QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: aegorenk, akhaitov, pemensik, pj.pandit, pwouters, security-response-team
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: unbound-1.6.6-5.el7_8 Doc Type: If docs needed, set a value
Doc Text:
An incomplete fix for CVE-2020-12662 was shipped for Unbound in Red Hat Enterprise Linux 7, as part of erratum RHSA-2020:2414. Vulnerable versions of Unbound could still amplify an incoming query into a large number of queries directed to a target, even with a lower amplification ratio compared to versions of Unbound that shipped before the mentioned erratum. This issue is about the incomplete fix for CVE-2020-12662, and it does not affect upstream versions of Unbound.
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Clone Of: Environment:
Last Closed: 2020-06-22 11:20:37 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: 1846424, 1846425, 1879512    
Bug Blocks: 1846017    

Description Riccardo Schirone 2020-06-10 15:33:38 UTC 
The fix for CVE-2020-12662 as shipped in Red Hat Enterprise Linux 7 (with version 1.6.6-4.el7_8 of Unbound delivered with https://access.redhat.com/errata/RHSA-2020:2414) is not complete and it still allows amplification of an incoming query into a bigger number of queries directed to a target. This issue is about the incomplete fix for CVE-2020-12662 and it does not affect upstream versions of unbound.

For more details about the original issue, refer to bug 1837597.
Comment 1 Riccardo Schirone 2020-06-10 15:36:05 UTC 
Even though the original fix for CVE-2020-12662 was incomplete, it slightly improved the situation over an unpatched version of Unbound, reducing the amplification ratio of a possible attack.
Comment 6 errata-xmlrpc 2020-06-22 10:06:30 UTC 
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 7

Via RHSA-2020:2642 https://access.redhat.com/errata/RHSA-2020:2642
Comment 7 Product Security DevOps Team 2020-06-22 11:20:37 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-2020-10772