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CVE-2009-3602· NVD / CVE Program· CNA redhat

Unbound before 1.3.4 does not properly verify signatures for NSEC3 records, which allows remote attackers to cause secure delegations to be

Unbound before 1.3.4 does not properly verify signatures for NSEC3 records, which allows remote attackers to cause secure delegations to be downgraded via DNS spoofing or other DNS-related attacks in conjunction with crafted delegation responses.

HighCVSS 7.5 · v2.0—No exploit Fix available
Published
Oct 13, 2009
Updated
Jun 16, 2026
EPSS
3.0% · 87th percentile
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Report tools

JSON

Action score

31

Monitor

Low priority for now.

CVSS
30 / 40 · 7.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
1 / 30 · 3.0%

Affected systems

VendorProduct
nlnetlabsunbound

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • nlnetlabs unboundup to 1.3.3 inclusive
  • nlnetlabs unbound0.0
  • nlnetlabs unbound0.09
  • nlnetlabs unbound0.1
  • nlnetlabs unbound0.10
  • nlnetlabs unbound0.11
  • nlnetlabs unbound0.2
  • nlnetlabs unbound0.3
  • nlnetlabs unbound0.4
  • nlnetlabs unbound0.5
  • nlnetlabs unbound0.6
  • nlnetlabs unbound0.7
  • nlnetlabs unbound0.7.1
  • nlnetlabs unbound0.7.2
  • nlnetlabs unbound0.8
  • nlnetlabs unbound1.0.0
  • nlnetlabs unbound1.0.1
  • nlnetlabs unbound1.0.2
  • nlnetlabs unbound1.1.0
  • nlnetlabs unbound1.1.1

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12unboundbefore 1.3.4-11.3.4-1
Debian:5.0unboundbefore 1.0.2-1+lenny11.0.2-1+lenny1

Other highest-scoring records for the same primary product.

  • CVE-2019-25042Unbound before 1.9.5 allows an out-of-bounds write via a compressed name in rdata_copy.
    40Plan
  • CVE-2019-25039Unbound before 1.9.5 allows an integer overflow in a size calculation in respip/respip.c.
    40Plan
  • CVE-2019-25038Unbound before 1.9.5 allows an integer overflow in a size calculation in dnscrypt/dnscrypt.c.
    40Plan
  • CVE-2019-25035Unbound before 1.9.5 allows an out-of-bounds write in sldns_bget_token_par.
    40Plan
  • CVE-2019-25034Unbound before 1.9.5 allows an integer overflow in sldns_str2wire_dname_buf_origin, leading to an out-of-bounds write.
    40Plan
  • CVE-2019-25033Unbound before 1.9.5 allows an integer overflow in the regional allocator via the ALIGN_UP macro.
    40Plan

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
debian:unbound1.3.4-1 · Debian:12Package 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.

EPSS, last 120 days

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.

Finders, 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
P · data can be read
Integrity
P · data or configuration can be modified
Availability
P · the service can be disrupted
Attack complexity
Low
Confidentiality impact
P
Integrity impact
P
Availability impact
P

CVSS vector

AV:N/AC:L/Au:N/C:P/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.

Noroxi analysis

No Noroxi analysis for this record yet

We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.

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Change log

  1. Fix✗ → ✓

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References

All records