CVE-2026-46580

Description

In Eclipse Theia versions prior to 1.71.0, files matching the pattern .prompts/*.prompttemplate in a workspace were automatically loaded and could override or extend the AI agent's system prompts. An attacker could craft a malicious repository containing prompt template files that, when the workspace was opened in Theia, replaced the AI's system instructions with attacker-controlled content (indirect prompt injection). Combined with other AI chat features available in untrusted workspaces, this enabled attack chains leading to data exfiltration via Markdown image rendering or arbitrary command execution via task definitions.

How to fix CVE-2026-46580

To remediate CVE-2026-46580, upgrade the affected package to a fixed version below.

• —upgrade to 1.71.0 or later
• —upgrade to 1.71.0 or later
• —upgrade to 1.71.0 or later
• —upgrade to 1.71.0 or later
• —upgrade to 1.71.0 or later
• —upgrade to 1.71.0 or later

Is CVE-2026-46580 being exploited?

No exploitation signal available. Neither CISA KEV nor a current EPSS score has been published for CVE-2026-46580.

Affected packages (6)

• from 0, < 1.71.0
• from 0, < 1.71.0
• from 0, < 1.71.0
• from 0, < 1.71.0
• from 0, < 1.71.0
• from 0, < 1.71.0

CVSS scores

References (6)

• ADVISORYnvd.nist.gov/vuln/detail/CVE-2026-46580
• PATCHgithub.com/eclipse-theia/theia
• WEBgithub.com/eclipse-theia/theia/commit/e3fdfe6992389bc5fa611058d00c39d7408508ed
• WEBgithub.com/eclipse-theia/theia/issues/16892
• WEB