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No exploitation reportedFix available

CVE-2020-19861

No exploitation reported by the sources we read.

  • Published2022-01-21
  • WeaknessCWE-125

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

When a zone file in ldns 1.7.1 is parsed, the function ldns_nsec3_salt_data is too trusted for the length value obtained from the zone file. When the memcpy is copied, the 0xfe - ldns_rdf_size(salt_rdf) byte data can be copied, causing heap overflow information leakage.

Timeline

dates in UTC
  1. 2022-01-2115:15CVE publishedNVD

Versions per branch

NVD
Nlnetlabs ldns
BranchAffectedFixed in
1.7= 1.7.1no fix published

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • ldnsUbuntu:Pro:22.04:LTSall versions · fixed in 1.7.1-2ubuntu4+esm1
  • ldnsUbuntu:Pro:20.04:LTSall versions · fixed in 1.7.0-4.1ubuntu1+esm1
  • ldnsUbuntu:Pro:16.04:LTSall versions · fixed in 1.6.17-8ubuntu0.1+esm1
  • ldnsUbuntu:18.04:LTSall versions · fixed in 1.7.0-3ubuntu4.1
  • ldnsSUSE:Linux Enterprise Real Time 15 SP2all versions · fixed in 1.7.0-4.6.1
  • ldnsSUSE:Linux Enterprise Module for Development Tools 15 SP3all versions · fixed in 1.7.0-4.6.1
  • ldnsSUSE:Linux Enterprise Module for Basesystem 15 SP3all versions · fixed in 1.7.0-4.6.1
  • ldnsopenSUSE:Tumbleweedall versions · fixed in 1.8.1-1.1

5 more package ranges on OSV.dev

Vendor advisories

  • CVE-2020-19861 Red Hat Product Security

    ldns: Heap out-of-bound read vulnerability in ldns_nsec3_salt_data function

Full record on NVD

Fix

No fix published by the sources we read yet. NVD record

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof of concept
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Published
2022-01-21
Last Modified
2026-06-17
NVD status
Modified
GitHub Advisory
GHSA-fhv5-v23r-vj74

Frequently asked questions

What is CVE-2020-19861?

When a zone file in ldns 1.7.1 is parsed, the function ldns_nsec3_salt_data is too trusted for the length value obtained from the zone file. When the memcpy is copied, the 0xfe - ldns_rdf_size(salt_rdf) byte data can be copied, causing heap overflow information leakage.

Is CVE-2020-19861 actively exploited?

Active exploitation of CVE-2020-19861 has not been confirmed. Its EPSS score was 1.5% on 2026-11-09, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2020-19861?

CVE-2020-19861 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

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