7.5

CVE-2018-10657: matrix synapse Improper Input Validation

CVSS: 7.5v3.0HighModified
AliasesGHSA-vmcc-4p4x-x7wgPYSEC-2026-846UBUNTU-CVE-2018-10657
Published 02-05-2018Last modified 16-09-2024
Open JSON

Vulnerability summary

CVE-2018-10657 is a high (CVSS 7.5) Improper Input Validation vulnerability in matrix synapse. EPSS estimates a 1.49% chance of exploitation in the next 30 days, higher than 73.7% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.5/10
010
High · v3.0 (NVD)
EPSS score
1.49%
0%100%
Low · -0.03 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 1 · Related 1
USN-6076-1

Timeline

  1. 02-05-2018
    PublishedVulnerability first disclosed.
  2. 16-09-2024
    Last modifiedVulnerability information updated.

Description

Matrix Synapse before 0.28.1 is prone to a denial of service flaw where malicious events injected with depth = 2^63 - 1 render rooms unusable, related to federation/federation_base.py and handlers/message.py, as exploited in the wild in April 2018.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

1.49%

Chance of exploitation in the next 30 days

Percentile

74%

Versus all other CVEs

30-day change

-0.03 pp

From 1.52% on 18-09-2026

18-09-202618-10-2026
EPSS score
1.49%

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

Debian1 product
  • matrix-synapse< 0.28.1+dfsg-1
Matrix1 product
PyPI1 product
  • matrix-synapse< 0.28.1
Ubuntu1 product
  • matrix-synapse< 0.24.0+dfsg-1ubuntu0.1~esm1

4 vendors · 4 products

References

12 links
Show all 12 references