4.3Medium
CVE-2026-91774
Yao through v1.0.0-rc22 authenticates but fails to authorize the GET /user/teams/:id endpoint, allowing any logged-in user to read full team records. Attackers can supply a known team identifier to retrieve sensitive team data including name, description, owner information, and settings without membership verification.
What this means for your business
- An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 4.3 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N- CVSS v4
- 5.3
- Weakness
- CWE-862
- Assigned by
- disclosure@vulncheck.com
Dates
- Published
- 2026-09-15
- Last modified
- 2026-09-17
- Sources
- NVD
References
- https://github.com/YaoApp/yao
- https://github.com/YaoApp/yao/blob/v1.0.0-rc22/openapi/oauth/providers/user/team.go#L37-L55
- https://github.com/YaoApp/yao/blob/v1.0.0-rc22/openapi/user/team.go#L80-L149
- https://github.com/YaoApp/yao/issues/1553
- https://www.vulncheck.com/advisories/yao-through-1.0.0-rc22-missing-authorization-via-openapi-team-endpoint