CVE-2019-5885

7.5 highEPSS 2.4%

Matrix Synapse before 0.34.0.1, when the macaroon_secret_key authentication parameter is not set, uses a predictable value to derive a secret key and other secrets which could allow remote attackers to impersonate users.

Severity

CVSS 3.0

7.5 high

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

EPSS: 2.4% chance of exploitation in the next 30 days; higher than 84% of CVEs (scores of 2026-10-31)
CWE: CWE-330
Published: 2019-03-21
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

fedoraproject:fedora
matrix:synapse

Packages (OSV)

Advisory	Ecosystem	Package	Affected	Fixed in
GHSA-jrqm-v8cv-53ww	PyPI	matrix-synapse	<0.34.0.1	0.34.0.1
PYSEC-2019-187	PyPI	matrix-synapse	<0.34.0.1	0.34.0.1

References

https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/32Y6KD3OAHCG5P33HC2QEX3NUZOSXCGZ/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VMCLO5PUPBA756UKY72PKUWL4RRM4W6K/
https://matrix.org/blog/2019/01/10/critical-security-update-synapse-0-34-0-1-synapse-0-34-1-1/
https://matrix.org/blog/2019/01/15/further-details-on-critical-security-update-in-synapse-affecting-all-versions-prior-to-0-34-1-cve-2019-5885/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/32Y6KD3OAHCG5P33HC2QEX3NUZOSXCGZ/

Check your stack JSON