DEBIAN-CVE-2026-32665

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Source
https://security-tracker.debian.org/tracker/CVE-2026-32665
Import Source
https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-32665.json
JSON Data
https://api.osv.dev/v1/vulns/DEBIAN-CVE-2026-32665
Upstream
Published
2026-07-22T14:17:18Z
Modified
2026-09-19T17:00:07Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
[none]
Details

In NLnet Labs Unbound 1.22.0 up to and including 1.25.1, when downstream DNS-over-QUIC (DoQ) is enabled, the first two bidirectional streams on a new QUIC connection (stream_id 0 and 4) bypass the per-stream 'quic-size' gate entirely, and large input buffers are allocated later, after only the 2-byte length prefix has been received from the initial streams. As a result, a remote client can make Unbound exceed the configured 'quic-size' limit with low-cost input. Using only one connection and two streams, each sending a declared 65535-byte length prefix and then holding the streams open, a client can already trivially make Unbound roughly allocate double that amount. This is a remote availability issue / memory-accounting bypass in the downstream DoQ implementation that leads to denial of service for new DoQ clients. This vulnerability needs Unbound to be compiled with DoQ support ('--with-libngtcp2') and the 'quic-port' to be configured for the listening interfaces.

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/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-32665.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/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-32665.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/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-32665.json"