lxd: Improperly Controlled Modification of Dynamically-Determined Object Attributes
CVE-2026-34179 is a critical-severity improperly controlled modification of dynamically-determined object attributes vulnerability in lxd from Canonical, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, without any action from a user. The record lists versions 5.0.7, 5.21.5, 6.8.0 as the first without the flaw, so updating lxd to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.28% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update lxd to 5.0.7 or 5.21.5 or 6.8.0, whichever matches your release line, or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Canonical | lxd | 4.12.0 up to, but not including, 5.0.7; 5.1.0 up to, but not including, 5.21.5; 6.0.0 up to, but not including, 6.8.0 | 5.0.7, 5.21.5, 6.8.0 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- HighAdministrator-level access is required first.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H. Scored by CNA (ubuntu.com).
Official description
In Canonical LXD versions 4.12 through 6.7, the doCertificateUpdate function in lxd/certificates.go does not validate the Type field when handling PUT/PATCH requests to /1.0/certificates/{fingerprint} for restricted TLS certificate users, allowing a remote authenticated attacker to escalate privileges to cluster admin.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improperly Controlled Modification of Dynamically-Determined Object Attributes
The product receives input from an upstream component that specifies multiple attributes, properties, or fields that are to be initialized or updated in an object, but it does not properly control which attributes can be modified.
How developers prevent this class of flaw
- If available, use features of the language or framework that allow specification of allowlists of attributes or fields that are allowed to be modified. If possible, prefer allowlists over denylists. For applications written with Ruby on Rails, use the attr_accessible (allowlist) or attr_protected (denylist) macros in each class that may be used in mass assignment.
- If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
- For any externally-influenced input, check the input against an allowlist of internal object attributes or fields that are allowed to be modified.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
- github.com/canonical/lxd/security/advisories/GHSA-c3h3-89qf-jqm5Exploit, Third Party Advisory
Patches and release notes
- github.com/canonical/lxd/pull/17936Issue Tracking
Other vulnerabilities in lxd
- 10.0 Critical severity
- 7.7 High severity
- 9.9 Critical severity
- 9.9 Critical severity
- 9.6 Critical severity
- 9.9 Critical severity
Recent Improperly Controlled Modification of Dynamically-Determined Object Attributes vulnerabilities
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 7.7 High severity
- 8.8 High severity
- 8.2 High severity
Spotted an error? Tell us.