🛡️ CVE-2026-45057 — matrix-sdk-ui
Description
matrix-sdk-ui: Incomplete edit validation
Impact
The message edit validation logic in the matrix-sdk-ui crate before 0.16.1 is missing a check: when replacing an encrypted event, the replacement event itself is not required to be encrypted. This enables a malicious homeserver administrator (or an actor with equivalent power) to impersonate or spoof messages as if they were sent by a victim user.
Patches
matrix-sdk-ui 0.16.1 fixes the message edit validation logic to align with the algorithm for replacement events[^1] described in the Matrix specification.
Workarounds
N/A
References
- Pull request: https://github.com/matrix-org/matrix-rust-sdk/pull/6454
For more information
If you have any questions or comments about this advisory, please email us at [security at matrix.org](mailto:[email protected]).
[^1]: https://spec.matrix.org/unstable/client-server-api/#validity-of-replacement-events
How this vulnerability can be exploited
This issue can be reached over the network, attack complexity is low, an attacker needs administrative privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality none, integrity high, availability none.
Weakness class
CVE-2026-45057 is classified as CWE-345: Insufficient Verification of Data Authenticity. Data is trusted without confirming it really came from the claimed source and was not altered.
Affected software
CVE-2026-45057 is recorded against 1 package.
- matrix-sdk-ui
Timeline and source
Published on 4 June 2026. No public exploit is currently recorded for this entry. Record sourced from OSV.
References
github.com (Web)
github.com (Web)
github.com (Package)
github.com (Web)
rustsec.org (Web)
Details
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N
Affected Packages
| Software | From version | Fixed in |
|---|---|---|
| matrix-sdk-ui | — | — |
References
Free Vulnerability Check
Is your site affected by CVE-2026-45057?
BotEraser helps you identify potentially vulnerable plugins and themes by checking your installation against CVE-2026-45057 and other known CVE records.
Scan My Site Free →No credit card required · Results in minutes
ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.