HOMEVULNERABILITIESCVE-2026-40243
MEDIUM

CVE-2026-40243

CWE-295Published: May 6, 2026· Updated: May 8, 2026

4.8
CVSS v3.1
EPSS:0.01%probability of exploitation in 30 daysPercentile:0.9th

Official Description

Incus is a system container and virtual machine manager. In versions before 7.0.0, broken TLS validation logic in the OVN database connection logic can allow connections to an attacker's OVN database. The OVN client implementations disable Go standard TLS server verification and replace it with custom peer-certificate verification logic. That replacement verifier does not anchor trust in the configured CA certificate. Instead, it constructs the verification root set from certificates supplied by the peer during the handshake, so the configured CA is parsed but not used as the trust anchor for the final verification decision.

In OVN-enabled deployments that use these SSL database connection paths, an attacker able to impersonate or intercept the OVN endpoint on the management network can present a rogue self-signed certificate chain, and Incus will accept this certificate as valid. This issue defeats the intended CA-based trust model for OVN database connections and permits endpoint impersonation by an active attacker in a suitable network position. This issue is fixed in version 7.0.0.

NVD Source

Technical Analysis

CVE-2026-40243 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityHigh
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityLow
IntegrityLow
AvailabilityNone
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N

Affected Vendors & Products

linuxcontainers1 product
incus
Source: NVD CPE · 1 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

All References (6)

Quick Facts

CVE IDCVE-2026-40243
CVSS Score4.8 / 10
SeverityMEDIUM
WeaknessCWE-295
CISA KEVNo
EPSS (30d)0.01%
Affected1 vendor
PublishedMay 6, 2026

Related CVEs (CWE-295)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2026-40243 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.