HOMEVULNERABILITIESCVE-2019-20397
HIGH

CVE-2019-20397

CWE-415Published: January 22, 2020· Updated: Jun 17, 2026

8.8
CVSS v3.1

Official Description

A double-free is present in libyang before v1.0-r1 in the function yyparse() when an organization field is not terminated. 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.

NVD Source

Technical Analysis

CVE-2019-20397 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation does not require any privileges, though user interaction (Required) is needed, which slightly reduces the risk of mass automated attacks.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 8.8.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionRequired
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected Vendors & Products

cesnet1 product(s)
libyang
Source: NVD CPE · 6 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

PATCHhttps://bugzilla.redhat.com/show_bug.cgi?id=1793928
PATCHhttps://github.com/CESNET/libyang/commit/88bd6c548ba79bce176cd875e9b56e7e0ef4d8d4
PATCHhttps://bugzilla.redhat.com/show_bug.cgi?id=1793928
PATCHhttps://github.com/CESNET/libyang/commit/88bd6c548ba79bce176cd875e9b56e7e0ef4d8d4
ADVISORYhttps://github.com/CESNET/libyang/compare/v0.16-r3...v1.0-r1
ADVISORYhttps://github.com/CESNET/libyang/issues/739
ADVISORYhttps://github.com/CESNET/libyang/compare/v0.16-r3...v1.0-r1
ADVISORYhttps://github.com/CESNET/libyang/issues/739

All References (10)

→
https://bugzilla.redhat.com/show_bug.cgi?id=1793928Issue Tracking · Patch · Third Party Advisory
→
https://github.com/CESNET/libyang/commit/88bd6c548ba79bce176cd875e9b56e7e0ef4d8d4Patch · Third Party Advisory
→
https://github.com/CESNET/libyang/compare/v0.16-r3...v1.0-r1Third Party Advisory
→
https://github.com/CESNET/libyang/issues/739Third Party Advisory
→
https://lists.debian.org/debian-lts-announce/2023/09/msg00019.html
→
https://bugzilla.redhat.com/show_bug.cgi?id=1793928Issue Tracking · Patch · Third Party Advisory
→
https://github.com/CESNET/libyang/commit/88bd6c548ba79bce176cd875e9b56e7e0ef4d8d4Patch · Third Party Advisory
→
https://github.com/CESNET/libyang/compare/v0.16-r3...v1.0-r1Third Party Advisory
→
https://github.com/CESNET/libyang/issues/739Third Party Advisory
→
https://lists.debian.org/debian-lts-announce/2023/09/msg00019.html

Quick Facts

CVE IDCVE-2019-20397
CVSS Score8.8 / 10
SeverityHIGH
WeaknessCWE-415
CISA KEVNo
Affected1 vendor(s)
PublishedJan 22, 2020

Related CVEs (CWE-415)

CVE-2018-0101
10.0
CVE-2024-45402
9.8
CVE-2024-35368
9.8
CVE-2019-8044
9.8
CVE-2024-11704
9.8
CVE-2005-1689
9.8

Recommended Actions

  • →Apply vendor patches immediately
  • →Monitor CVE-2019-20397 in threat intel feeds
  • →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.
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