CVE-2026-55428: Coder: Route hijacking through lack of validation of agent-supplied AllowedIPs in tailnet coordinator
Affected: coder · Exploitation: unlikely (under 1%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 35% of scored CVEs
DescriptionCVE.org
Coder allows organizations to provision remote development environments via Terraform. Prior to versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2, the tailnet coordinator validates that an agent's `Addresses` derive from its authenticated UUID but applies no equivalent check to `AllowedIPs`. The coordinator forwards agent-supplied `AllowedIPs` verbatim to tunnel peers which install them into the WireGuard peer configuration. The fix in versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2 validates each `AllowedIPs` prefix against the authenticating agent's UUID just like `Addresses`. As a workaround, monitor coordinator logs for agents advertising unexpected `AllowedIPs` prefixes.
Affected products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- coder · coder>= 2.34.0, < 2.34.2; >= 2.33.0, < 2.33.8; >= 2.30.0, < 2.32.7; < 2.29.17
On the Atlas
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CoverageNo articles yet
No CyberSIXT article names CVE-2026-55428 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.
References
- NVD entrynvd.nist.gov
- CVE recordcve.org
- Weakness CWE-863cwe.mitre.org
- github.com/coder/coder/security/advisories/GHSA-wrq8-fcv5-8hvpgithub.com
- github.com/coder/coder/pull/26144github.com
- github.com/coder/coder/releases/tag/v2.29.17github.com
- github.com/coder/coder/releases/tag/v2.32.7github.com
- github.com/coder/coder/releases/tag/v2.33.8github.com
- github.com/coder/coder/releases/tag/v2.34.2github.com