GitHub Copilot 1.372.0 allows filesystem access outside of a workspace folder (without user approval) via a file-handler URI parameter to f…

published 2026-06-22 4mo ago modified 2026-10-12 28d ago also EUVD-2025-210298

cvss: 7.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.2%; EPSS 1.2% chance of exploitation in 30 days, percentile 67%
public exploits: 0; none known

GitHub Copilot 1.372.0 allows filesystem access outside of a workspace folder (without user approval) via a file-handler URI parameter to fetch_webpage. Therefore, exfiltration could occur if there is indirect prompt injection.

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CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: partial
Assessed: 4mo ago (2026-06-22)

Exploit prediction

1.18% chance of exploitation in the next 30 days, higher than 67% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

blindcyber.com https://blindcyber.com/2025/10/28/copilot-fun/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CNA	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Classification

Weakness

CWE-552 Files or Directories Accessible to External Parties

References

blindcyber.com /2025/10/28/copilot-fun/
exploit, third-party-advisory
github.com /microsoft/vscode-copilot-chat/
product
github.com /microsoft/vscode/blob/03baef1008086ed4960042fa463e570072173bb5/src/vs/workbench/contrib/chat/electron-browser
product

Sources

CVE List CVE-2025-66389
NVD CVE-2025-66389

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.