CVE-2021-213336.1MediumCWE-74

CVE-2021-21333: HTML injection in email and account expiry notifications

matrix-org · synapse

Fixed in 1.27.0 · Affected: matrix-org synapse before 1.27.0 · Exploitation: possible (1 to 10%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

1.4%probability of exploitation in the next 30 days

72nd percentile

050100

Higher than 72% of scored CVEs

6.1MediumCVSS 3.1

LowMediumHighCrit.

DescriptionCVE.org

Synapse is a Matrix reference homeserver written in python (pypi package matrix-synapse). Matrix is an ecosystem for open federated Instant Messaging and VoIP. In Synapse before version 1.27.0, the notification emails sent for notifications for missed messages or for an expiring account are subject to HTML injection. In the case of the notification for missed messages, this could allow an attacker to insert forged content into the email. The account expiry feature is not enabled by default and the HTML injection is not controllable by an attacker. This is fixed in version 1.27.0.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

matrix-org · synapse< 1.27.0

On the Atlas

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Open the Atlas

Exploitation: Possible (1 to 10%). EPSS between 1% and 10%.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Injection · Injection and Smuggling
Vendor: matrix-org
Published: March 2021
Band: Possible (1 to 10%), March 2021

CoverageNo articles yet

No CyberSIXT article names CVE-2021-21333 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.