DEBIAN-CVE-2026-39402

See a problem?
Please try reporting it to the source first.
Source
https://security-tracker.debian.org/tracker/CVE-2026-39402
Import Source
https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-39402.json
JSON Data
https://api.osv.dev/v1/vulns/DEBIAN-CVE-2026-39402
Upstream
  • CVE-2026-39402
Published
2026-05-05T21:16:22.537Z
Modified
2026-05-17T23:03:37.458950Z
Severity
  • 6.5 (Medium) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H CVSS Calculator
Summary
[none]
Details

lxc is a Linux container runtime. In the setuid helper lxc-user-nic, the delete path contains a logic flaw in the find_line() function that allows an unprivileged user to delete OVS-attached network interfaces belonging to other users. When lxc-user-nic delete scans its NIC database to authorize a deletion request, the interface name comparison can set the authorization flag based on a name match alone, even when the ownership, type, and link fields in that database entry belong to a different user. The vulnerable check sits after the goto next label handling, meaning it is reachable on lines where earlier ownership checks failed or were skipped. Because nothing downstream of this authorization signal re-verifies that the matched database line actually belongs to the caller, an unprivileged attacker with a valid lxc-usernet policy entry can trigger deletion of another user's OVS port on the same bridge. This is limited to multi-tenant environments using lxc-user-nic with OpenVSwitch bridges. The impact is denial of service - one tenant can repeatedly disconnect networking from containers run by another tenant on shared infrastructure. This is patched in version 7.0.0.

References

Affected packages

Debian:11 / lxc

Package

Name
lxc
Purl
pkg:deb/debian/lxc?arch=source

Affected ranges

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

Affected versions

1:4.*
1:4.0.6-2
1:4.0.6-2+deb11u1
1:4.0.6-2+deb11u2
1:4.0.10-1
1:4.0.10-2
1:4.0.11-1~exp1
1:4.0.11-1~exp2
1:4.0.11-1~exp3
1:4.0.11-1~exp4
1:4.0.11-1
1:5.*
1:5.0.1-1
1:5.0.1-2
1:5.0.2-1
1:5.0.3-1
1:5.0.3-2
1:5.0.3-2.1~exp1
1:5.0.3-2.1
1:5.0.3-3
1:6.*
1:6.0.0a-1
1:6.0.1-1
1:6.0.2-1
1:6.0.3-1
1:6.0.3-2
1:6.0.4-1
1:6.0.4-2
1:6.0.4-3
1:6.0.4-4
1:6.0.5-1
1:6.0.5-2
1:6.0.6-1
1:6.0.6-2
1:6.0.6-3
1:7.*
1:7.0.0-1

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-39402.json"

Debian:12 / lxc

Package

Name
lxc
Purl
pkg:deb/debian/lxc?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1:5.0.2-1+deb12u4

Affected versions

1:5.*
1:5.0.2-1
1:5.0.2-1+deb12u1
1:5.0.2-1+deb12u2
1:5.0.2-1+deb12u3

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-39402.json"

Debian:13 / lxc

Package

Name
lxc
Purl
pkg:deb/debian/lxc?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1:6.0.4-4+deb13u3

Affected versions

1:6.*
1:6.0.4-4
1:6.0.4-4+deb13u1
1:6.0.4-4+deb13u2

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-39402.json"

Debian:14 / lxc

Package

Name
lxc
Purl
pkg:deb/debian/lxc?arch=source

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Fixed
1:7.0.0-1

Affected versions

1:6.*
1:6.0.4-4
1:6.0.5-1
1:6.0.5-2
1:6.0.6-1
1:6.0.6-2
1:6.0.6-3

Ecosystem specific 

{
    "urgency": "not yet assigned"
}

Database specific

source 
"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2026-39402.json"