Bug 1954796 (CVE-2019-25038)

Summary:	CVE-2019-25038 unbound: integer overflow in a size calculation in dnscrypt/dnscrypt.c
Product:	[Other] Security Response	Reporter:	Guilherme de Almeida Suckevicz <gsuckevi>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	aegorenk, akhaitovich, paul.wouters, pemensik, pj.pandit
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	unbound 1.9.6	Doc Type:	If docs needed, set a value
Doc Text:	A flaw was found in unbound. An integer overflow in dnsc_load_local_data function may lead to a buffer overflow of the allocated buffer if the size can be controlled by an attacker. The highest threat from this vulnerability is to data confidentiality and integrity as well as service availability.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-05-18 20:39:10 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:	1859933, 1968662, 1968663, 1968664
Bug Blocks:	1954811

Description Guilherme de Almeida Suckevicz 2021-04-28 19:06:22 UTC

Unbound before 1.9.5 allows an integer overflow in a size calculation in dnscrypt/dnscrypt.c.

Reference:
https://ostif.org/our-audit-of-unbound-dns-by-x41-d-sec-full-results/

Comment 1 Riccardo Schirone 2021-05-06 11:32:12 UTC

Upstream patch:
https://github.com/NLnetLabs/unbound/commit/02080f6b180232f43b77f403d0c038e9360a460f

Comment 3 Riccardo Schirone 2021-05-06 14:53:13 UTC

Statement:

There is no available reproducer or proof of concept for this issue, nor it was ever proven the integer overflow can lead to a buffer overflow in practice. Indeed in the original report this issue was considered one that might not be triggered and for this reason its Impact is Moderate.

Comment 5 errata-xmlrpc 2021-05-18 15:37:48 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2021:1853 https://access.redhat.com/errata/RHSA-2021:1853

Comment 6 Product Security DevOps Team 2021-05-18 20:39:10 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-2019-25038

Comment 8 errata-xmlrpc 2022-02-22 15:13:51 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.2 Extended Update Support

Via RHSA-2022:0632 https://access.redhat.com/errata/RHSA-2022:0632