CVE-2026-46354 Coder: PKCS#7 signature bypass in Azure instance identity allows unauthenticated agent token theft

Critical 9.1 Published 7 Jul 2026 Updated 8 Jul 2026

Attackers can steal agent session tokens by forging PKCS#7 signatures in Azure instance identity validation, bypassing authentication to access victim workspaces.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2026-46354?

CVE-2026-46354 is a critical authentication bypass vulnerability in coder, published on 7 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

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`.

Weakness: CWE-347

Which versions are affected by CVE-2026-46354?

16 open source packages ship an affected version, including github.com/coder/coder/v2 and github.com/coder/coder. It affects 1 product.

Package	Affected	Fixed in
`github.com/coder/coder/v2` Go	All versions	`2.24.5, 2.29.13, 2.30.8, 2.31.12, 2.32.2, 2.33.3`
`github.com/coder/coder/v2` Go	All versions	`2.24.5`
`github.com/coder/coder/v2` Go	All versions	`2.24.5`
`github.com/coder/coder/v2` Go	From `2.29.0`	`2.29.13`
`github.com/coder/coder/v2` Go	From `2.29.0`	`2.29.13`
`github.com/coder/coder/v2` Go	From `2.30.0`	`2.30.8`

10 more packages

`github.com/coder/coder/v2` Go	From `2.30.0`	`2.30.8`
`github.com/coder/coder/v2` Go	From `2.31.0`	`2.31.12`
`github.com/coder/coder/v2` Go	From `2.31.0`	`2.31.12`
`github.com/coder/coder/v2` Go	From `2.32.0-rc.0`	`2.32.2`
`github.com/coder/coder/v2` Go	From `2.32.0-rc.0`	`2.32.2`
`github.com/coder/coder/v2` Go	From `2.33.0-rc.0`	`2.33.3`
`github.com/coder/coder/v2` Go	From `2.33.0-rc.0`	`2.33.3`
`github.com/coder/coder` Go	All versions	None
`github.com/coder/coder` Go	All versions to `0.27.3`	None
`github.com/coder/coder` Go	All versions to `0.27.3`	None

Products include Coder Coder.

How do I fix CVE-2026-46354?

Upgrade github.com/coder/coder/v2 to a fixed version for your release line: 2.24.5, 2.29.13, 2.30.8 or 2.31.12.

Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.

Is CVE-2026-46354 being exploited?

There is no known exploitation of CVE-2026-46354 in the wild and no public exploit code.

Sources

Also known as GHSA-6x44-w3xg-hqqf, GO-2026-5196.