CVE-2026-55434: coder DoS — Fix

Description

Coder allows organizations to provision remote development environments via Terraform. Starting in version 2.33.0 and prior to versions 2.33.8 and 2.34.2, AI Bridge provider handlers read request bodies with `io.ReadAll` without a maximum size so an authenticated user with AI Bridge access could send an arbitrarily large body and exhaust memory. Exploitation requires authenticated access to the AI Bridge endpoints and the impact is limited to availability (denial of service). Versions 2.33.8 and 2.34.2 patch the issue. No known workarounds are available.

Is your site exposed to CVE-2026-55434?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

6.5

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS — Exploit Prediction

0.0055

Probability of exploitation

0.43%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-770 CWE-770

Affected Products

Vendor	Product	Versions
coder	coder	2.33.0 — 2.33.8
coder	coder	2.34.0 — 2.34.2

References

Advisories & Patches

https://github.com/coder/coder/pull/26164 https://github.com/coder/coder/security/advisories/GHSA-f5vp-w269-392g

Other References

https://github.com/coder/coder/releases/tag/v2.33.8 https://github.com/coder/coder/releases/tag/v2.34.2

Frequently Asked Questions

What is CVE-2026-55434? +

Coder allows organizations to provision remote development environments via Terraform. Starting in version 2.33.0 and prior to versions 2.33.8 and 2.34.2, AI Bridge provider handlers read request bodies with `io.ReadAll` without a maximum size so an authenticated user with AI Bridge access could send an arbitrarily large body and exhaust memory. Exploitation requires authenticated access to the AI Bridge endpoints and the impact is limited to availability (denial of service). Versions 2.33.8 and 2.34.2 patch the issue. No known workarounds are available. It has a CVSS v3.1 base score of 6.5 (MEDIUM).

How severe is CVE-2026-55434? +

CVE-2026-55434 has a CVSS v3.1 score of 6.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0055, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-55434? +

CVE-2026-55434 affects products from coder, specifically: coder. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-55434? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2026-39313

mcp-framework is a framework for building Model Context Protocol (MCP) servers. In versions 0.2.21 and below, the readRequestBody() function in …

CVE-2026-35469

spdystream is a Go library for multiplexing streams over SPDY connections. In versions 0.5.0 and below, the SPDY/3 frame parser …

CVE-2026-39803

Allocation of Resources Without Limits or Throttling vulnerability in mtrudel bandit allows unauthenticated remote denial of service via memory exhaustion. …

CVE-2026-39804

Allocation of Resources Without Limits or Throttling vulnerability in mtrudel bandit allows unauthenticated remote denial of service via memory exhaustion …

CVE-2026-32688

Allocation of Resources Without Limits or Throttling vulnerability in elixir-plug plug_cowboy allows unauthenticated remote denial of service via atom table …

CVE-2026-10573

A denial-of-service security issue exists in 1734 POINT I/O™ module. The security issue stems from improper handling of crafted CIP …

CVE-2026-55434