GHSA-h58c-xccx-75m3: Anthropic Python

### Summary The `ApplicationName` and `LogoURL` appearance settings were rendered into HTML output without sufficient escaping which let a highly privileged Owner-role user inject HTML into the Coder dashboard and SMTP notification emails. > **Note:** Exploitation requires the `Owner` role which...

Full CISO analysis pending enrichment.

What systems are affected?

Package	Ecosystem	Vulnerable Range	Patched
Anthropic Python	go	>= 2.34.0, < 2.34.2	`2.34.2`
3.8K 6.4K dependents Pushed 5d ago 90% patched ~11d to patch Full package profile →

Do you use Anthropic Python? You're affected.

How severe is it?

CVSS 3.1

3.4 / 10

EPSS

N/A

Exploitation Status

No known exploitation

Sophistication

N/A

What is the attack surface?

AV Network

AC Low

PR High

UI Required

S Changed

C None

I Low

A None

What should I do?

Patch available

Update Anthropic Python to version 2.34.2

Which compliance frameworks are affected?

Compliance analysis pending. Sign in for full compliance mapping when available.

Frequently Asked Questions

What is GHSA-h58c-xccx-75m3?

### Summary The `ApplicationName` and `LogoURL` appearance settings were rendered into HTML output without sufficient escaping which let a highly privileged Owner-role user inject HTML into the Coder dashboard and SMTP notification emails. > **Note:** Exploitation requires the `Owner` role which already holds full administrative control of the deployment so practical impact is limited. ### Impact An Owner-role user could store HTML markup in the `ApplicationName` or `LogoURL` appearance settings that later rendered in the dashboard and in SMTP notification emails which results in stored HTML injection against other users of the deployment. Exploitation requires the highly privileged `Owner` role. ### Patches The fix escapes the `ApplicationName` and `LogoURL` appearance values in HTML output before rendering. The fix was backported to all supported release lines: | Release line | Patched version | |---|---| | 2.34 | [v2.34.2](https://github.com/coder/coder/releases/tag/v2.34.2) | | 2.33 | [v2.33.8](https://github.com/coder/coder/releases/tag/v2.33.8) | | 2.32 | [v2.32.7](https://github.com/coder/coder/releases/tag/v2.32.7) | | 2.29 (ESR) | [v2.29.17](https://github.com/coder/coder/releases/tag/v2.29.17) | ### Workarounds Restrict the `Owner` role to trusted administrators. ### References - Fix: #25804 ### Credits We'd like to thank Anthropic's Security Team (ANT-2026-22453) for independently disclosing this issue!

Is GHSA-h58c-xccx-75m3 actively exploited?

No confirmed active exploitation of GHSA-h58c-xccx-75m3 has been reported, but organizations should still patch proactively.

How to fix GHSA-h58c-xccx-75m3?

Update to patched version: Anthropic Python 2.34.2.

What is the CVSS score for GHSA-h58c-xccx-75m3?

GHSA-h58c-xccx-75m3 has a CVSS v3.1 base score of 3.4 (LOW).

What are the technical details?

Original Advisory

### Summary The `ApplicationName` and `LogoURL` appearance settings were rendered into HTML output without sufficient escaping which let a highly privileged Owner-role user inject HTML into the Coder dashboard and SMTP notification emails. > **Note:** Exploitation requires the `Owner` role which already holds full administrative control of the deployment so practical impact is limited. ### Impact An Owner-role user could store HTML markup in the `ApplicationName` or `LogoURL` appearance settings that later rendered in the dashboard and in SMTP notification emails which results in stored HTML injection against other users of the deployment. Exploitation requires the highly privileged `Owner` role. ### Patches The fix escapes the `ApplicationName` and `LogoURL` appearance values in HTML output before rendering. The fix was backported to all supported release lines: | Release line | Patched version | |---|---| | 2.34 | [v2.34.2](https://github.com/coder/coder/releases/tag/v2.34.2) | | 2.33 | [v2.33.8](https://github.com/coder/coder/releases/tag/v2.33.8) | | 2.32 | [v2.32.7](https://github.com/coder/coder/releases/tag/v2.32.7) | | 2.29 (ESR) | [v2.29.17](https://github.com/coder/coder/releases/tag/v2.29.17) | ### Workarounds Restrict the `Owner` role to trusted administrators. ### References - Fix: #25804 ### Credits We'd like to thank Anthropic's Security Team (ANT-2026-22453) for independently disclosing this issue!

Weaknesses (CWE)

CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') Primary

CWE-74 — Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection'): The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component.

[Requirements] Programming languages and supporting technologies might be chosen which are not subject to these issues.
[Implementation] Utilize an appropriate mix of allowlist and denylist parsing to filter control-plane syntax from all input.

Source: MITRE CWE corpus.