How severe is CVE-2020-19860?

CVE-2020-19860 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2020-19860 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-19860?

CVE-2020-19860 affects Nlnetlabs Ldns. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-19860?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-19860 published?

CVE-2020-19860 was published on 2022-01-21 and last updated on 2026-06-17.

CVE-2020-19860

CVE-2020-19860 is a medium-severity vulnerability in Nlnetlabs Ldns with a CVSS 3.x base score of 6.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-125.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (67th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Nlnetlabs Ldns
Published: 2022-01-21
Last modified: 2026-06-17

Description

When ldns version 1.7.1 verifies a zone file, the ldns_rr_new_frm_str_internal function has a heap out of bounds read vulnerability. An attacker can leak information on the heap by constructing a zone file payload.

Frequently asked questions

What is CVE-2020-19860?: When ldns version 1.7.1 verifies a zone file, the ldns_rr_new_frm_str_internal function has a heap out of bounds read vulnerability. An attacker can leak information on the heap by constructing a zone file payload.
How severe is CVE-2020-19860?: CVE-2020-19860 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2020-19860 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-19860?: CVE-2020-19860 affects Nlnetlabs Ldns. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-19860?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-19860 published?: CVE-2020-19860 was published on 2022-01-21 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:nlnetlabs:ldns:1.7.1:*:*:*:*:*:*:*

More vulnerabilities in Nlnetlabs Ldns

CVE-2017-1000232 — Critical (CVSS 9.8): A double-free vulnerability in str2host.c in ldns 1.7.0 have unspecified impact and attack vectors.
CVE-2017-1000231 — Critical (CVSS 9.8): A double-free vulnerability in parse.c in ldns 1.7.0 have unspecified impact and attack vectors.
CVE-2026-10846 — High (CVSS 7.5): NLnet Labs ldns 1.2.0 up to and including versions 1.9.0, when used in applications as (stub) resolver over UDP, lacks…
CVE-2020-19861 — High (CVSS 7.5): When a zone file in ldns 1.7.1 is parsed, the function ldns_nsec3_salt_data is too trusted for the length value…
CVE-2011-3581 — Medium (CVSS 6.8): Heap-based buffer overflow in the ldns_rr_new_frm_str_internal function in ldns before 1.6.11 allows remote attackers…
CVE-2009-1086 — Medium (CVSS 6.4): Heap-based buffer overflow in the ldns_rr_new_frm_str_internal function in ldns 1.4.x allows remote attackers to cause…

All CVEs affecting Nlnetlabs Ldns →

Other CWE-125 (Out-of-bounds Read) vulnerabilities

CVE-2026-24826 — Critical (CVSS 10.0): Out-of-bounds Write, Divide By Zero, NULL Pointer Dereference, Use of Uninitialized Resource, Out-of-bounds Read,…
CVE-2024-22004 — Critical (CVSS 10.0): Due to length check, an attacker with privilege access on a Linux Nonsecure operating system can trigger a…
CVE-2021-41556 — Critical (CVSS 10.0): sqclass.cpp in Squirrel through 2.2.5 and 3.x through 3.1 allows an out-of-bounds read (in the core interpreter) that…
CVE-2021-21777 — Critical (CVSS 10.0): An information disclosure vulnerability exists in the Ethernet/IP UDP handler functionality of EIP Stack Group OpENer…
CVE-2017-14451 — Critical (CVSS 10.0): An exploitable out-of-bounds read vulnerability exists in libevm (Ethereum Virtual Machine) of CPP-Ethereum. A…
CVE-2013-0767 — Critical (CVSS 10.0): The nsSVGPathElement::GetPathLengthScale function in Mozilla Firefox before 18.0, Firefox ESR 10.x before 10.0.12 and…

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