Aggregate DNS name chained pointer decompression work leads to degradation of service.
Severity and exploitation
KEV coverage does not rule out exploitation.
Assessment vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:LSeverity
medium5.3CVSS measures technical severity, not the likelihood of an attack.
Known exploitation
Not listed in the checked CISA KEV catalog
Absence from CISA KEV does not rule out attacks.
Public exploit
Not established by this record
Missing evidence does not mean no public exploit exists.
Remediation
Source guidance available
Review the recorded instructions. Guidance may be a workaround rather than a fixed version.
What this means
Unbound versions up to 1.26.1 have no aggregate decompression-work budget, allowing a malicious actor with recursive-query access to degrade performance with specially crafted replies. The vulnerability is due to allocation of resources without limits. An attacker can exploit this with control of a delegated authority.
Summarized by @cf/meta/llama-3.3-70b-instruct-fp8-fast. Verify details against the original sources.Attack conditions
No attack-condition excerpt has been identified here. Review the full source description and references for authentication, network access, and configuration requirements.
Review supporting sources →Affected versions
Check the exact model, release, and any platform requirements against your installation.
NLnet Labs · NLnet Labs
Unbound
1 range
NLnet Labs · NLnet Labs
Unbound
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affected
0 → before 1.26.2
semver versions
Other versions: unaffected
What to do
Compare your installed product and version with the affected versions above. A matching product name alone does not confirm exposure.
This issue is fixed starting with version 1.26.2
cve.new guidance unless attributed to a publisher. This page does not inspect your installation.
Public exploit evidence
No public exploit reference is identified in the imported evidence. This is not a claim that no exploit exists.
Original source description
Read the full publisher description
NLnet Labs Unbound up to and including version 1.26.1 limits compression-pointer traversal for each individual domain-name operation but has no aggregate inbound decompression-work budget. Many chained compression pointers in a message results in a lot of CPU usage following them. A malicious actor with recursive-query access and control of an ordinarily delegated authority that serves specially crafted replies can exploit the vulnerability and degrade Unbound's general performance.
References
1 sourcesInside the record
Evidence available
Describes the evidence in this view, not whether the product is safe.
Original records
CVE-2026-96405View the latest unmodified CVE JSON from the official source. It may be newer than this imported page.
cve.new JSON →Underlying weaknesses
The source’s classification of what caused the vulnerability.
Contributing organizations · 2
Assigning organization
Additional data publisher
Timeline
All times UTCAdvisory published
Publication date supplied by the source.
Source updated
Latest modification date supplied by the source.
Last imported by cve.new
Latest catalog import, not the date we first saw this advisory.
What changed
Follow changesLarge field values are marked as truncated previews. Original source snapshots remain retained.