Moderate severityNVD Advisory· Published Mar 26, 2021· Updated Aug 3, 2024
HTML injection in email and account expiry notifications
CVE-2021-21333
Description
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.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected packages
Versions sourced from the GitHub Security Advisory.
| Package | Affected versions | Patched versions |
|---|---|---|
matrix-synapsePyPI | < 1.27.0 | 1.27.0 |
Affected products
2- Range: < 1.27.0
Patches
Vulnerability mechanics
References
9- github.com/advisories/GHSA-c5f8-35qr-q4fmghsaADVISORY
- lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEY/mitrevendor-advisoryx_refsource_FEDORA
- nvd.nist.gov/vuln/detail/CVE-2021-21333ghsaADVISORY
- github.com/matrix-org/synapse/commit/e54746bdf7d5c831eabe4dcea76a7626f1de73dfghsax_refsource_MISCWEB
- github.com/matrix-org/synapse/pull/9200ghsax_refsource_MISCWEB
- github.com/matrix-org/synapse/releases/tag/v1.27.0ghsax_refsource_MISCWEB
- github.com/matrix-org/synapse/security/advisories/GHSA-c5f8-35qr-q4fmghsax_refsource_CONFIRMWEB
- github.com/pypa/advisory-database/tree/main/vulns/matrix-synapse/PYSEC-2021-134.yamlghsaWEB
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TNNAJOZNMVMXM6AS7RFFKB4QLUJ4IFEYghsaWEB
News mentions
0No linked articles in our index yet.