High severity · published Apr 27, 2021
CVE-2019-25036
Unbound before 1.9.5 allows an assertion failure and denial of service in synth_cname
7.5
CVSS
2.1%
EPSS
No
On KEV
Description
Unbound before 1.9.5 allows an assertion failure and denial of service in synth_cname. NOTE: The vendor disputes that this is a vulnerability. Although the code may be vulnerable, a running Unbound installation cannot be remotely or locally exploited
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.1% · higher than 81% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0 · source: NVD
UN
Unbound · Nlnetlabs
before 1.9.5 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-25036
CVE.org
https://www.cve.org/CVERecord?id=CVE-2019-25036
Mailing List
https://lists.debian.org/debian-lts-announce/2021/05/msg00007.html
Patch
https://ostif.org/our-audit-of-unbound-dns-by-x41-d-sec-full-results/
Third Party Advisory
https://security.netapp.com/advisory/ntap-20210507-0007/
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