CVE-2026-3351VulnerabilityPublished 3 Mar 2026Updated 5 Mar 2026

CVE-2026-3351: Canonical lxd · Missing Authorization

Affects Canonical lxdSource CVE Database V5

Not known to be exploited · CVSS 2.1 Low.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 4.0 base score

2.1Low

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N/E:P

Base metrics

Attack Vector: Network
Attack Complexity: Low
Attack Requirements: None
Privileges Required: Low
User Interaction: None
Vulnerable system confidentiality: Low
Vulnerable system integrity: None
Vulnerable system availability: None
Subsequent system confidentiality: Low
Subsequent system integrity: None
Subsequent system availability: None

Threat metrics

Exploit Maturity: POC

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, up to and including the entire Internet. Such a vulnerability is often termed “remotely exploitable” and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Attack Requirements: None: The successful attack does not depend on the deployment and execution conditions of the vulnerable system. The attacker can expect to be able to reach the vulnerability and execute the exploit under all or most instances of the vulnerability.
Privileges Required: Low: The attacker requires privileges that provide basic capabilities that are typically limited to settings and resources owned by a single low-privileged user. Alternatively, an attacker with Low privileges has the ability to access only non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without interaction from any human user, other than the attacker.
Vulnerable system confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the Vulnerable System.
Vulnerable system integrity: None: There is no loss of integrity within the Vulnerable System.
Vulnerable system availability: None: There is no impact to availability within the Vulnerable System.
Subsequent system confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the Subsequent System.
Subsequent system integrity: None: There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System.
Subsequent system availability: None: There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.
Exploit Maturity: POC: Based on threat intelligence sources each of the following must apply: · Proof-of-concept is publicly available · No knowledge of reported attempts to exploit this vulnerability · No knowledge of publicly available solutions used to simplify attempts to exploit the vulnerability

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 3 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
Canonicallxd	Affected =6.6	Fixed in–
GitHubcanonical/lxd`pkg:github/canonical/lxd`Other threats	Affected =6.6	Fixed in–
GitHublxd`pkg:github/lxd`Other threats	Affected =6.6	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

To mitigate CVE-2026-3351, organizations should implement the following specific measures: 1) Restrict API access to trusted and minimal sets of users by enforcing strict authentication and role-based access controls, ensuring only fully authorized administrators can access sensitive endpoints like /1.0/certificates. 2) Monitor and audit API usage logs to detect any unauthorized or suspicious access attempts to certificate information. 3) Upgrade to a patched version of Canonical LXD once available, as vendors typically address missing authorization issues promptly. 4) If immediate patching is not possible, consider network segmentation or firewall rules to limit access to the LXD API server to trusted management networks only. 5) Review and harden container management policies to minimize the number of users with API access. 6) Conduct internal security assessments to verify that no other API endpoints suffer from similar missing authorization issues. These steps go beyond generic advice by focusing on access control tightening, monitoring, and network-level protections tailored to the LXD environment.

Description

Improper authorization in the API endpoint GET /1.0/certificates in Canonical LXD 6.6 on Linux allows an authenticated, restricted user to enumerate all certificate fingerprints trusted by the lxd server.

Impact

The primary impact of CVE-2026-3351 is information disclosure, allowing an authenticated restricted user to enumerate all trusted certificate fingerprints on the LXD server. While this does not directly compromise system confidentiality, integrity, or availability, it can facilitate further attacks by revealing the trust infrastructure and potentially aiding attackers in crafting targeted attacks or impersonation attempts. Organizations relying on LXD 6.6 for container management may face increased risk of reconnaissance by malicious insiders or compromised accounts. The impact is limited by the requirement for authentication and the low sensitivity of the disclosed information relative to direct system compromise. However, in high-security environments where certificate trust information is sensitive, this vulnerability could contribute to a broader attack chain. Since no known exploits exist in the wild and the vulnerability does not allow privilege escalation or remote code execution, the overall risk remains low but should not be ignored in secure deployments.

CWE-862Missing Authorization (opens in a new tab)
Class weaknessLikelihood of exploit: HighCWE Top 25 (2025): #4OWASP Top 10 A01:2025: Broken Access Control (opens in a new tab)
The product does not perform an authorization check when an actor attempts to access a resource or perform an action.
Architecture and Design
Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) to enforce the roles at the appropriate boundaries.
Architecture and Design
Ensure that access control checks are performed related to the business logic. These checks may be different than the access control checks that are applied to more generic resources such as files, connections, processes, memory, and database records.
Architecture and Design · Libraries or Frameworks
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
OWASP Cheat Sheets
Authorization (opens in a new tab)
OWASP ASVS 4.0.3
V8.3.8 (opens in a new tab)
V13.4.2 (opens in a new tab)
V7.2.2 (opens in a new tab)
Attack patterns
Exploitation of Thunderbolt Protection Flaws (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 5 Mar 2026, 18:35 UTC

WeaknessesCWE-862

Technical details

References

Community reviews

Related threats