7.5

CVE-2025-66622: matrix-org matrix-rust-sdk

CVSS: 7.5v3.1HighAnalyzed
AliasesGHSA-jj6p-3m75-g2p3RUSTSEC-2025-0135
Published 09-12-2025Last modified 09-12-2025
Open JSON

Vulnerability summary

CVE-2025-66622 is a high (CVSS 7.5) vulnerability in matrix-org matrix-rust-sdk. EPSS estimates a 0.41% chance of exploitation in the next 30 days, higher than 34.1% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.1 (NVD)
EPSS score
0.41%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 09-12-2025
    PublishedVulnerability first disclosed.
  2. 09-12-2025
    Last modifiedVulnerability information updated.

Description

matrix-sdk-base is the base component to build a Matrix client library. Versions 0.14.1 and prior are unable to handle responses that include custom m.room.join_rules values due to a serialization bug. This can be exploited to cause a denial-of-service condition, if a user is invited to a room with non-standard join rules, the crate's sync process will stall, preventing further processing for all rooms. This is fixed in version 0.16.0.

CVSS metrics

4 scores · 3 sources · 2 versions

EPSS trend

Probability

0.41%

Chance of exploitation in the next 30 days

Percentile

34%

Versus all other CVEs

30-day change

0.00 pp

From 0.41% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.41%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Crates.Io1 product
  • matrix-sdk-base< 0.16.0 | ≥ 0.0.0-0, < 0.16.0
Matrix1 product
Matrix-org1 product

3 vendors · 3 products

References

7 links