Case wayback-copilot-lassoModel & data leakUnited States
Copilot serves code from 20,000 GitHub repos that were made private, via Bing cache
Lasso Security found Copilot still returned content from over 20,000 repositories of 16,000+ organisations that had been made private or deleted, because Bing cached them while public. Microsoft disabled cache links.
MediumAttack on AIStatus: ContainedVerified case file
Open in the interactive mapCite this case
- Reported
- Feb 26, 2025
- Location
- United States
- Target
- Microsoft Copilot and GitHub repository owners
- Severity
- Medium
- Triggered by
- Lasso Security
- Actor type
- Security researchers
- Reported loss
- None reported
- CVE
- None
What happened
Lasso Security found Copilot still returned content from over 20,000 repositories of 16,000+ organisations that had been made private or deleted, because Bing cached them while public. Microsoft disabled cache links.
Impact: Secrets and private code remained retrievable; Lasso said Copilot still had some access after the cache change
Who triggered it
Actor: Lasso Security
Attribution: Responsible disclosure to Microsoft in November 2024
Motive: Security research
How it happened
Attack vector: Copilot retrieval grounded on stale Bing index of formerly public pages
Root cause: Search cache not purged when repositories changed visibility
Timeline
- Lasso reports the issue to Microsoft
- Public disclosure; Microsoft had removed Bing cached links
Response
Microsoft disabled Bing cache link feature; Lasso said the fix was partial
Current status: Contained
Sources (open in a new tab)
- TechCrunch techcrunch.com
- SC World scworld.com
Cite this case
Copilot serves code from 20,000 GitHub repos that were made private, via Bing cache. AI Threat Watch, case wayback-copilot-lasso, Feb 26, 2025. https://aithreat.io/cases/wayback-copilot-lasso/
Permanent link: https://aithreat.io/cases/wayback-copilot-lasso/