CVE-2026-55427: 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, `coder config-ssh` wrote server-supplie

highCVSS 8.3CVE-2026-55427

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, coder config-ssh wrote server-supplied SSH settings (HostnameSuffix, SSHConfigOptions) into the user's ~/.ssh/config without sanitizing embedded newlines or restricting directives so a malicious or compromised Coder server could inject arbitrary SSH configuration. Practical exploitation requires control of the server-supplied values through a malicious or compromised deployment, a man-in-the-middle position or admin access to the HostnameSuffix and SSHConfigOptions settings. The fix in versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2 validates HostnameSuffix and SSHConfigOptions against a strict character set that rejects newlines and other control characters. As a workaround, inspect coder config-ssh --dry-run output before applying changes.

Details

Source: NVD Recent CVEs (US · database · site)
Severity: high — CVSS 8.3
Published: 2026-07-08
Last updated: 2026-07-08
Exploitation: Not in CISA KEV at last sync

Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-55427

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-554270.47% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 37% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-55427	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

highGHSA-mcqq-fqgf-rxwm: Coder vulnerable to SSH config injection via unsanitized server-supplied values in `coder…ghsa

Recent advisories for Coder

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

mediumCVE-2026-55438: Coder allows organizations to provision remote development environments via Terraform. Prior t…nvd · 2026-07-08
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mediumCVE-2026-55433: Coder allows organizations to provision remote development environments via Terraform. Prior t…nvd · 2026-07-08
mediumCVE-2026-55432: Coder allows organizations to provision remote development environments via Terraform. Prior t…nvd · 2026-07-08
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