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NVD / CVE Program· CNA GitHub_M

CVE-2026-23953: Incus container environment configuration newline injection

Noroxi assessment

Priority: Monitor (action score 34/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.49% (FIRST EPSS).
  • Someone on the same network segment can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: lxd (Debian:12) 5.0.2-5+deb12u3; incus (Debian:13) 6.0.4-2+deb13u4; lxd (Debian:13) 5.0.2+git20231211.1364ae4-9+deb13u3.

Low priority for now. Upgrade to lxd (Debian:12) 5.0.2-5+deb12u3; incus (Debian:13) 6.0.4-2+deb13u4; lxd (Debian:13) 5.0.2+git20231211.1364ae4-9+deb13u3 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Incus is a system container and virtual machine manager. In versions 6.20.0 and below, a user with the ability to launch a container with a custom YAML configuration (e.g a member of the ‘incus’ group) can create an environment variable containing newlines, which can be used to add additional configuration items in the container’s lxc.conf due to newline injection. This can allow adding arbitrary lifecycle hooks, ultimately resulting in arbitrary command execution on the host. Exploiting this issue on IncusOS requires a slight modification of the payload to change to a different writable directory for the validation step (e.g /tmp). This can be confirmed with a second container with /tmp mounted from the host (A privileged action for validation only). A fix is planned for versions 6.0.6 and 6.21.0, but they have not been released at the time of publication.

HighCVSS 8.7 · v3.1—No exploit Fix available
Published
Jan 22, 2026
Updated
Jun 17, 2026
EPSS
0.4% · 42th percentile

Report tools

JSON

Action score

34

Monitor

Low priority for now.

CVSS
34 / 40 · 8.7 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.4%

CISA SSVC decision

Exploitation
proof of concept
Automatable
no
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · GitHub_M
8.7
NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

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When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
linuxcontainersincus

Affected versions

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

  • linuxcontainers incusup to 6.0.5 inclusive
  • linuxcontainers incus6.1.0 and later · before 6.21.0

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

  • lxc incus

    • >= 6.1.0, <= 6.20.0, <= 6.0.5affected

Package-level exposure

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

EcosystemPackageAffected rangeFix
Debian:12lxdfrom 0—
Debian:12lxdbefore 5.0.2-5+deb12u35.0.2-5+deb12u3
Debian:13incusbefore 6.0.4-2+deb13u46.0.4-2+deb13u4
Debian:13lxdbefore 5.0.2+git20231211.1364ae4-9+deb13u35.0.2+git20231211.1364ae4-9+deb13u3
Debian:14incusbefore 6.0.5-86.0.5-8
Gogithub.com/lxc/incusfrom 0—
Gogithub.com/lxc/incus/v6from 6.1.0—
Gogithub.com/lxc/incus/v6before 6.21.06.21.0
openSUSE:Tumbleweedincusbefore 6.22-1.16.22-1.1

Same product

linuxcontainers: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-33897Incus vulnerable to arbitrary file read and write through pongo templates
    39Monitor
  • CVE-2026-33945Abitrary file write through systemd-creds option
    38Monitor
  • CVE-2026-33898Local Incus UI web server vulnerable to nuthentication bypass
    35Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2025-64507Nov 10, 2025 · Incus vulnerable to local privilege escalation through custom storage volumes
    34Monitor
  • Later →CVE-2026-23954Jan 22, 2026 · Incus container image templating arbitrary host file read and write
    34Monitor
  • Later →CVE-2026-33542Mar 26, 2026 · Incus does not verify combined fingerprint when downloading images from simplestreams servers
    22Monitor

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:incus6.0.4-2+deb13u4 · Debian:13Package registry (OSV)
debian:lxd5.0.2+git20231211.1364ae4-9+deb13u3 · Debian:13Package registry (OSV)
Go:github.com/lxc/incus/v66.21.0Package registry (OSV)
opensuse:incus6.22-1.1 · openSUSE:TumbleweedPackage 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.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Credits

All researchers

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

  • Someone on the same network segment can trigger it.
  • A low-privileged account is enough.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
none

Impact can extend beyond the vulnerable component (scope changes).

Attack vector
Adjacent
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Changed
Confidentiality impact
High
Integrity impact
High
Availability impact
None

Weakness class (CWE)

CWE-93 · Improper Neutralization of CRLF Sequences ('CRLF Injection')

CVSS vector

CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

ATT&CK techniques

—

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (1 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records