CVE-2021-29432Medium· 5.3▾ SunlitMalicious users could abuse Sydent to control the content of invitation emails
▾ Sunlit zone — Low / medium · no exploitation signal
impact 29.2 · likelihood 0.2 · exploitation 0
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Exploit-prediction probability, daily snapshots since Sep 12.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via OSV
Last analysed / modified upstream
0.9%
A malicious user could abuse Sydent to send out arbitrary emails from the Sydent email address. This could be used to construct plausible phishing emails, for example.
Fixed in 4469d1d, 6b405a8, 65a6e91.
Note that these patches include changes to the default email templates. If these templates have been locally modified, they must also be updated.
If you have any questions or comments about this advisory, email us at [email protected].
matrix-sydent < 2.3.0Upgrade to a patched release:
matrix-sydent 2.3.0Connected by shared product, vendor, weakness, or advisory.
CVE-2021-29430High· 7.5Sydent vulnerable to denial of service attack via memory exhaustion
CVE-2021-29431High· 7.7SSRF in Sydent due to missing validation of hostnames
CVE-2021-29433Medium· 4.3Sydent DoS (via resource exhaustion) due to improper input validation
CVE-2023-38686Critical· 9.3Sydent does not verify email server certificates
CVE-2019-11842High· 7.5matrix-sydent and matrix-synapse Use Cryptographically Weak PRNG
CVE-2019-11340Medium· 5.9Matrix Sydent mishandles emails