MEDIUM · 6.5

CVE-2026-63095

Dendrite through 0.13.8 contains an improper authorization vulnerability in the Matrix Client-Server API that allows any authenticated local user to delete third-party identifier bindings belonging to...

Vulnerability Description

Dendrite through 0.13.8 contains an improper authorization vulnerability in the Matrix Client-Server API that allows any authenticated local user to delete third-party identifier bindings belonging to other users by submitting an arbitrary address and medium to the account deletion endpoint without ownership verification. Attackers can exploit the unverified Forget3PID handler to remove a victim's email or MSISDN binding and subsequently rebind the address through an identity server to hijack the victim's password reset flow.

CVSS Score

6.5

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
HIGH
Availability
NONE

Related Weaknesses (CWE)

References

FAQ

What is CVE-2026-63095?

CVE-2026-63095 is a vulnerability with a CVSS score of 6.5 (MEDIUM). Dendrite through 0.13.8 contains an improper authorization vulnerability in the Matrix Client-Server API that allows any authenticated local user to delete third-party identifier bindings belonging to...

How severe is CVE-2026-63095?

CVE-2026-63095 has been rated MEDIUM with a CVSS base score of 6.5/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-63095?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.