coder: Improper Verification of Cryptographic Signature
CVE-2026-46354 is a critical-severity improper verification of cryptographic signature vulnerability in coder, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected coder versions: >= 2.33.0-rc.0, < 2.33.3; >= 2.32.0-rc.0, < 2.32.2; >= 2.31.0, < 2.31.12, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.32% 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
- Check which version of coder you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Coder | coder | >= 2.33.0-rc.0, < 2.33.3; >= 2.32.0-rc.0, < 2.32.2; >= 2.31.0, < 2.31.12; >= 2.30.0, < 2.30.8; >= 2.29.0, < 2.29.13; < 2.24.5 | Not stated |
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
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N. Scored by CNA (github.com).
Official description
Coder allows organizations to provision remote development environments via Terraform. In versions prior tp 2.24.5, 2.29.13, 2.30.8, 2.31.12, 2.32.2, and 2.33.3, `azureidentity.Validate()` verifies that the PKCS#7 signer certificate chains to a trusted Azure CA but never verifies the PKCS#7 signature itself. An attacker can embed a legitimate Azure certificate alongside arbitrary content e.g. `{"vmId":"<target>"}` and the forged `vmId` will be accepted returning the victim workspace agent's session token. No authentication is required. The attacker only needs to know a target VM's `vmId` which is a `UUIDv4`. That's a practical limitation which would typically require prior access to be exploited. Versions 2.24.5, 2.29.13, 2.30.8, 2.31.12, 2.32.2, and 2.33.3 patch the issue. As a workaround, reconfigure any Azure templates to use token authentication rather than `azure-instance-identity`.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Verification of Cryptographic Signature
The product does not verify, or incorrectly verifies, the cryptographic signature for data.
More Improper Verification of Cryptographic Signature vulnerabilities (CWE-347)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- github.com/coder/coder/pull/25286Issue Tracking
- github.com/coder/coder/releases/tag/v2.24.5Release Notes
- github.com/coder/coder/releases/tag/v2.29.13Release Notes
- github.com/coder/coder/releases/tag/v2.30.8Release Notes
- github.com/coder/coder/releases/tag/v2.31.12Release Notes
- github.com/coder/coder/releases/tag/v2.32.2Release Notes
- github.com/coder/coder/releases/tag/v2.33.3Release Notes
Other vulnerabilities in coder
- 7.7 High severity
- 7.7 High severity
- 8.3 High severity
- 7.4 High severity
- 8.7 High severity
- 8.2 High severity
Recent Improper Verification of Cryptographic Signature vulnerabilities
- 8.1 High severity
- 7.2 High severity
- 7.5 High severity
- 7.5 High severity
- 8.1 High severity
- 7.5 High severity
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