DEBIAN-CVE-2026-42955

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Source
https://security-tracker.debian.org/tracker/CVE-2026-42955
Import Source
https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-42955.json
JSON Data
https://api.test.osv.dev/v1/vulns/DEBIAN-CVE-2026-42955
Upstream
Published
2026-07-22T14:17:18Z
Modified
2026-09-19T16:00:08Z
Severity
  • 3.7 (Low) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N CVSS Calculator
Summary
[none]
Details

In NLnet Labs Unbound 1.16.2 up to and including 1.25.1, a similar vulnerability as with CVE-2026-40622 in the 'ghost domain names' family of attacks was found in Unbound that could extend the ghost domain window by up to one cached TTL configured value for A/AAAA glue records. Similar to other 'ghost domain names' attacks, an adversary needs to control a (ghost) zone and be able to query a vulnerable Unbound. A single client A/AAAA query can cause Unbound to overwrite the cached expired parent-side glue rrset and essentially extend the ghost domain window by up to one cached TTL configured value ('cache-max-ttl'). In configurations where 'harden-referral-path: yes' is used (non-default configuration), no client query is required since Unbound implicitly performs that query. This is a variant of CVE-2026-40622 which only addressed the NS query.

References

Affected packages

Debian:12 / unbound

Package

Name
unbound
Purl
pkg:deb/debian/unbound?arch=source&distro=bookworm

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

1.*
1.17.1-2
1.17.1-2+deb12u1
1.17.1-2+deb12u2
1.17.1-2+deb12u3
1.17.1-2+deb12u4
1.17.1-2+loong64
1.18.0-1
1.18.0-2
1.19.1-1
1.19.2-1
1.20.0-1
1.21.1-1
1.22.0-1
1.22.0-2
1.23.1-1
1.24.0-1
1.24.0-2
1.24.1-1
1.24.1-2
1.24.2-1
1.25.0-1
1.25.1-1
1.25.2-1
1.26.0-1
1.26.0-2
1.26.1-1

Ecosystem specific 

{
    "urgency":  "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-42955.json"

Debian:13 / unbound

Package

Name
unbound
Purl
pkg:deb/debian/unbound?arch=source&distro=trixie

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
1.26.1-0+deb13u1

Affected versions

1.*
1.22.0-2
1.22.0-2+deb13u1
1.22.0-2+deb13u2
1.22.0-2+deb13u3
1.23.1-1
1.24.0-1
1.24.0-2
1.24.1-1
1.24.1-2
1.24.2-1
1.25.0-1
1.25.1-1
1.25.2-1
1.26.0-1
1.26.0-2

Ecosystem specific 

{
    "urgency":  "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-42955.json"

Debian:14 / unbound

Package

Name
unbound
Purl
pkg:deb/debian/unbound?arch=source&distro=forky

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
1.25.2-1

Affected versions

1.*
1.22.0-2
1.23.1-1
1.24.0-1
1.24.0-2
1.24.1-1
1.24.1-2
1.24.2-1
1.25.0-1
1.25.1-1

Ecosystem specific 

{
    "urgency":  "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-42955.json"