CVE-2026-63095 (GCVE-0-2026-63095)
Vulnerability from cvelistv5 – Published: 2026-07-17 15:27 – Updated: 2026-07-28 01:49 X_Open Source Unsupported When Assigned
VLAI
EPSS
VEX
Title
Dendrite 0.13.8 Improper Authorization via POST account/3pid/delete Endpoint
Summary
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.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-17 16:00 UTC
CWE
- CWE-639 - Authorization Bypass Through User-Controlled Key
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/geo-chen/oss/blob/main/dendrit… | technical-descriptionexploit |
| https://www.vulncheck.com/advisories/dendrite-imp… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| matrix-org | dendrite |
Affected:
0 , ≤ 0.13.8
(semver)
cpe:2.3:a:matrix:dendrite:*:*:*:*:*:*:*:* |
Date Public
2026-07-16 00:00
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.