Heap-based buffer overflow in the ldns_rr_new_frm_str_internal function in ldns 1.4.x allows remote attackers to cause a denial of service (
Heap-based buffer overflow in the ldns_rr_new_frm_str_internal function in ldns 1.4.x allows remote attackers to cause a denial of service (memory corruption) and possibly execute arbitrary code via a DNS resource record (RR) with a long (1) class field (clas variable) and possibly (2) TTL field.
- Published
- Mar 25, 2009
- Updated
- Jun 16, 2026
- EPSS
- 3.5% · 89th percentile
- CWE
- CWE-399
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Report tools
Action score
26
Monitor
Low priority for now.
- CVSS
- 25 / 40 · 6.4 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 3.5%
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpAffected systems
| Vendor | Product | CPE |
|---|---|---|
| nlnetlabs | ldns | cpe:2.3:a:nlnetlabs:ldns |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- nlnetlabs ldns1.4.0
- nlnetlabs ldns1.4.1
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | ldns | before 1.5.1-1 | 1.5.1-1 |
| Debian:5.0 | ldns | before 1.4.0-1+lenny1 | 1.4.0-1+lenny1 |
Same product
nlnetlabs: all recordsOther highest-scoring records for the same primary product.
- CVE-2017-1000232A double-free vulnerability in str2host.c in ldns 1.7.0 have unspecified impact and attack vectors.40Plan
- CVE-2017-1000231A double-free vulnerability in parse.c in ldns 1.7.0 have unspecified impact and attack vectors.40Plan
- CVE-2026-10846Insufficient verification that responses belong to a query32Monitor
- CVE-2020-19861When 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.30Monitor
- CVE-2011-3581Heap-based buffer overflow in the ldns_rr_new_frm_str_internal function in ldns before 1.6.11 allows remote attackers to cause a denial of s28Monitor
- CVE-2020-19860When 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.26Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| debian:ldns | 1.5.1-1 · Debian:12 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- P · data or configuration can be modified
- Availability
- P · the service can be disrupted
- Attack complexity
- Low
- Confidentiality impact
- None
- Integrity impact
- P
- Availability impact
- P
Weakness class (CWE)
CWE-399 · Resource Management ErrorsCVSS vector
AV:N/AC:L/Au:N/C:N/I:P/A:P
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- lists.opensuse.org/opensuse-security-announce/2009-05/msg00000.html
- secunia.com/advisories/35013
- secunia.com/advisories/35065
- www.debian.org/security/2009/dsa-1795
- www.nlnetlabs.nl/bugs/show_bug.cgi?id=232
- www.nlnetlabs.nl/svn/ldns/tags/release-1.5.0/Changelog
- www.openwall.com/lists/oss-security/2009/03/24/4
- www.securityfocus.com/bid/34233
Vendor advisories and official records. Exploit/PoC links are deliberately left out.