High severity · published Jan 22, 2020
CVE-2019-20393
A double-free is present in libyang before v1.0-r1 in the function yyparse() when an empty description is used
8.8
CVSS
2.8%
EPSS
No
On KEV
Description
A double-free is present in libyang before v1.0-r1 in the function yyparse() when an empty description is used. Applications that use libyang to parse untrusted input yang files may be vulnerable to this flaw, which would cause a crash or potentially code execution.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.8% · higher than 87% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Libyang · Cesnet
0.11; 0.11; 0.12; 0.12; 0.13; 0.13; +5 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-20393
CVE.org
https://www.cve.org/CVERecord?id=CVE-2019-20393
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=1793930
Patch
https://github.com/CESNET/libyang/commit/d9feacc4a590d35dbc1af21caf9080008b4450ed
Third Party Advisory
https://github.com/CESNET/libyang/compare/v0.16-r3...v1.0-r1
Exploit
https://github.com/CESNET/libyang/issues/742
lists.debian.org
https://lists.debian.org/debian-lts-announce/2023/09/msg00019.html
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