GHSA-7QW2-F75V-62F7
Vulnerability from github – Published: 2026-07-06 21:12 – Updated: 2026-07-06 21:12Summary
The AgentLogLine dashboard component instantiated ansi-to-html without escapeXML: true and inserted the result via dangerouslySetInnerHTML so HTML embedded in workspace agent log lines was rendered as live markup. Server-side sanitization did not neutralize HTML metacharacters.
Note: Exploitation requires a victim to view attacker-controlled agent logs in the dashboard.
Impact
A user who could run a workspace could emit arbitrary HTML into agent logs; when another user, including an administrator, viewed the workspace page, it rendered in their session. Content Security Policy blocked inline scripts but an attacker could still inject a meta refresh redirect, style rules for UI redressing or CSS-based exfiltration or external img beacons. This required workspace-owner access and a victim viewing the page.
Patches
The fix enables escapeXML: true so HTML metacharacters are escaped before DOM insertion.
The fix was backported to all supported release lines:
| Release line | Patched version |
|---|---|
| 2.34 | v2.34.2 |
| 2.33 | v2.33.8 |
| 2.32 | v2.32.7 |
| 2.29 (ESR) | v2.29.17 |
Workarounds
None.
Resources
- Fix: #25808
Credits
Coder would like to thank Anthropic's Security Team (ANT-2026-22449) for independently disclosing this issue!
{
"affected": [
{
"package": {
"ecosystem": "Go",
"name": "github.com/coder/coder/v2"
},
"ranges": [
{
"events": [
{
"introduced": "2.34.0"
},
{
"fixed": "2.34.2"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Go",
"name": "github.com/coder/coder/v2"
},
"ranges": [
{
"events": [
{
"introduced": "2.33.0"
},
{
"fixed": "2.33.8"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Go",
"name": "github.com/coder/coder/v2"
},
"ranges": [
{
"events": [
{
"introduced": "2.30.0"
},
{
"fixed": "2.32.7"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Go",
"name": "github.com/coder/coder/v2"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "2.29.17"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-55437"
],
"database_specific": {
"cwe_ids": [
"CWE-79"
],
"github_reviewed": true,
"github_reviewed_at": "2026-07-06T21:12:56Z",
"nvd_published_at": null,
"severity": "MODERATE"
},
"details": "### Summary\n\nThe `AgentLogLine` dashboard component instantiated `ansi-to-html` without `escapeXML: true` and inserted the result via `dangerouslySetInnerHTML` so HTML embedded in workspace agent log lines was rendered as live markup. Server-side sanitization did not neutralize HTML metacharacters.\n\n\u003e **Note:** Exploitation requires a victim to view attacker-controlled agent logs in the dashboard.\n\n### Impact\n\nA user who could run a workspace could emit arbitrary HTML into agent logs; when another user, including an administrator, viewed the workspace page, it rendered in their session. Content Security Policy blocked inline scripts but an attacker could still inject a `meta refresh` redirect, `style` rules for UI redressing or CSS-based exfiltration or external `img` beacons. This required workspace-owner access and a victim viewing the page.\n\n### Patches\n\nThe fix enables `escapeXML: true` so HTML metacharacters are escaped before DOM insertion.\n\nThe fix was backported to all supported release lines:\n\n| Release line | Patched version |\n|---|---|\n| 2.34 | [v2.34.2](https://github.com/coder/coder/releases/tag/v2.34.2) |\n| 2.33 | [v2.33.8](https://github.com/coder/coder/releases/tag/v2.33.8) |\n| 2.32 | [v2.32.7](https://github.com/coder/coder/releases/tag/v2.32.7) |\n| 2.29 (ESR) | [v2.29.17](https://github.com/coder/coder/releases/tag/v2.29.17) |\n\n### Workarounds\n\nNone.\n\n### Resources\n\n- Fix: #25808\n\n### Credits\n\nCoder would like to thank Anthropic\u0027s Security Team (ANT-2026-22449) for independently disclosing this issue!",
"id": "GHSA-7qw2-f75v-62f7",
"modified": "2026-07-06T21:12:56Z",
"published": "2026-07-06T21:12:56Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/coder/coder/security/advisories/GHSA-7qw2-f75v-62f7"
},
{
"type": "WEB",
"url": "https://github.com/coder/coder/pull/25808"
},
{
"type": "PACKAGE",
"url": "https://github.com/coder/coder"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N",
"type": "CVSS_V3"
}
],
"summary": "Coder vulnerable to stored HTML injection via workspace agent logs in AgentLogLine component"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.