← Back

Matrix

matrix

81 CVEs • 16 products

Products (16)

Click to collapse
Toggle
Synapse
synapse
Sydent
sydent
Olm
olm
Element
element
Dendrite
dendrite
React Sdk
react_sdk
Hookshot
hookshot

CVEs (81)

CVE
VENDORS
PRODUCTS
UPDATED
PUBLISHED
CVSS
1Matrix
1Sydent
Jun 17, 2026
Apr 15, 2021
N/A· v4
6.5 MEDIUM· v3
4.0 MEDIUM· v2
Sydent is a reference Matrix identity server. Sydent can be induced to send HTTP GET requests to internal systems, due to lack of parameter validation or IP address blacklisting. It is not possible to exfiltrate data or...Show more
Sydent is a reference Matrix identity server. Sydent can be induced to send HTTP GET requests to internal systems, due to lack of parameter validation or IP address blacklisting. It is not possible to exfiltrate data or control request headers, but it might be possible to use the attack to perform an internal port enumeration. This issue has been addressed in in 9e57334, 8936925, 3d531ed, 0f00412. A potential workaround would be to use a firewall to ensure that Sydent cannot reach internal HTTP resources.Show less
1Matrix
1Sydent
Jun 17, 2026
Apr 15, 2021
N/A· v4
7.5 HIGH· v3
5.0 MEDIUM· v2
Sydent is a reference Matrix identity server. Sydent does not limit the size of requests it receives from HTTP clients. A malicious user could send an HTTP request with a very large body, leading to memory exhaustion and...Show more
Sydent is a reference Matrix identity server. Sydent does not limit the size of requests it receives from HTTP clients. A malicious user could send an HTTP request with a very large body, leading to memory exhaustion and denial of service. Sydent also does not limit response size for requests it makes to remote Matrix homeservers. A malicious homeserver could return a very large response, again leading to memory exhaustion and denial of service. This affects any server which accepts registration requests from untrusted clients. This issue has been patched by releases 89071a1, 0523511, f56eee3. As a workaround request sizes can be limited in an HTTP reverse-proxy. There are no known workarounds for the problem with overlarge responses.Show less
1Matrix
1Sydent
Jun 17, 2026
Apr 15, 2021
N/A· v4
4.3 MEDIUM· v3
4.0 MEDIUM· v2
Sydent is a reference Matrix identity server. In Sydent versions 2.2.0 and prior, sissing input validation of some parameters on the endpoints used to confirm third-party identifiers could cause excessive use of disk spa...Show more
Sydent is a reference Matrix identity server. In Sydent versions 2.2.0 and prior, sissing input validation of some parameters on the endpoints used to confirm third-party identifiers could cause excessive use of disk space and memory leading to resource exhaustion. A patch for the vulnerability is in version 2.3.0. No workarounds are known to exist.Show less
2Fedoraproject
Matrix
2Fedora
Synapse
Jun 17, 2026
Apr 12, 2021
N/A· v4
6.5 MEDIUM· v3
4.3 MEDIUM· v2
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 1.28.0 Synapse is missing input va...Show more
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 1.28.0 Synapse is missing input validation of some parameters on the endpoints used to confirm third-party identifiers could cause excessive use of disk space and memory leading to resource exhaustion. Note that the groups feature is not part of the Matrix specification and the chosen maximum lengths are arbitrary. Not all clients might abide by them. Refer to referenced GitHub security advisory for additional details including workarounds.Show less
2Fedoraproject
Matrix
2Fedora
Synapse
Jun 17, 2026
Apr 12, 2021
N/A· v4
6.3 MEDIUM· v3
4.9 MEDIUM· v2
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 1.28.0 requests to user provided d...Show more
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 1.28.0 requests to user provided domains were not restricted to external IP addresses when transitional IPv6 addresses were used. Outbound requests to federation, identity servers, when calculating the key validity for third-party invite events, sending push notifications, and generating URL previews are affected. This could cause Synapse to make requests to internal infrastructure on dual-stack networks. See referenced GitHub security advisory for details and workarounds.Show less
2Fedoraproject
Matrix
2Fedora
Synapse
Jun 17, 2026
Apr 12, 2021
N/A· v4
6.5 MEDIUM· v3
4.0 MEDIUM· v2
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 1.28.0 Synapse is missing input va...Show more
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 1.28.0 Synapse is missing input validation of some parameters on the endpoints used to confirm third-party identifiers could cause excessive use of disk space and memory leading to resource exhaustion. Note that the groups feature is not part of the Matrix specification and the chosen maximum lengths are arbitrary. Not all clients might abide by them. Refer to referenced GitHub security advisory for additional details including workarounds.Show less
2Fedoraproject
Matrix
2Fedora
Synapse
Jun 17, 2026
Mar 26, 2021
N/A· v4
6.1 MEDIUM· v3
2.6 LOW· v2
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 se...Show more
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.Show less
2Fedoraproject
Matrix
2Fedora
Synapse
Jun 17, 2026
Mar 26, 2021
N/A· v4
8.2 HIGH· v3
4.3 MEDIUM· v2
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 password reset endpoin...Show more
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 password reset endpoint served via Synapse was vulnerable to cross-site scripting (XSS) attacks. The impact depends on the configuration of the domain that Synapse is deployed on, but may allow access to cookies and other browser data, CSRF vulnerabilities, and access to other resources served on the same domain or parent domains. This is fixed in version 1.27.0.Show less
2Fedoraproject
Matrix
2Fedora
Synapse
Jun 17, 2026
Feb 26, 2021
N/A· v4
6.5 MEDIUM· v3
4.3 MEDIUM· v2
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 1.25.0, a malicious homeserver cou...Show more
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 1.25.0, a malicious homeserver could redirect requests to their .well-known file to a large file. This can lead to a denial of service attack where homeservers will consume significantly more resources when requesting the .well-known file of a malicious homeserver. This affects any server which accepts federation requests from untrusted servers. Issue is resolved in version 1.25.0. As a workaround the `federation_domain_whitelist` setting can be used to restrict the homeservers communicated with over federation.Show less
2Fedoraproject
Matrix
2Fedora
Synapse
Jun 17, 2026
Feb 26, 2021
N/A· v4
6.1 MEDIUM· v3
5.8 MEDIUM· v2
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 1.25.0, requests to user provided...Show more
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 1.25.0, requests to user provided domains were not restricted to external IP addresses when calculating the key validity for third-party invite events and sending push notifications. This could cause Synapse to make requests to internal infrastructure. The type of request was not controlled by the user, although limited modification of request bodies was possible. For the most thorough protection server administrators should remove the deprecated `federation_ip_range_blacklist` from their settings after upgrading to Synapse v1.25.0 which will result in Synapse using the improved default IP address restrictions. See the new `ip_range_blacklist` and `ip_range_whitelist` settings if more specific control is necessary.Show less
2Fedoraproject
Matrix
2Fedora
Synapse
Jun 17, 2026
Dec 9, 2020
N/A· v4
6.5 MEDIUM· v3
4.0 MEDIUM· v2
Matrix is an ecosystem for open federated Instant Messaging and VoIP. Synapse is a reference "homeserver" implementation of Matrix. A malicious or poorly-implemented homeserver can inject malformed events into a room by...Show more
Matrix is an ecosystem for open federated Instant Messaging and VoIP. Synapse is a reference "homeserver" implementation of Matrix. A malicious or poorly-implemented homeserver can inject malformed events into a room by specifying a different room id in the path of a `/send_join`, `/send_leave`, `/invite` or `/exchange_third_party_invite` request. This can lead to a denial of service in which future events will not be correctly sent to other servers over federation. This affects any server which accepts federation requests from untrusted servers. The Matrix Synapse reference implementation before version 1.23.1 the implementation is vulnerable to this injection attack. Issue is fixed in version 1.23.1. As a workaround homeserver administrators could limit access to the federation API to trusted servers (for example via `federation_domain_whitelist`).Show less
2Fedoraproject
Matrix
2Fedora
Synapse
Jun 17, 2026
Nov 24, 2020
N/A· v4
7.5 HIGH· v3
5.0 MEDIUM· v2
Matrix Synapse before 1.20.0 erroneously permits non-standard NaN, Infinity, and -Infinity JSON values in fields of m.room.member events, allowing remote attackers to execute a denial of service attack against the federa...Show more
Matrix Synapse before 1.20.0 erroneously permits non-standard NaN, Infinity, and -Infinity JSON values in fields of m.room.member events, allowing remote attackers to execute a denial of service attack against the federation and common Matrix clients. If such a malformed event is accepted into the room's state, the impact is long-lasting and is not fixed by an upgrade to a newer version, requiring the event to be manually redacted instead. Since events are replicated to servers of other room members, the impact is not constrained to the server of the event sender.Show less
1Matrix
1Synapse
Jun 17, 2026
Oct 19, 2020
N/A· v4
6.1 MEDIUM· v3
4.3 MEDIUM· v2
AuthRestServlet in Matrix Synapse before 1.21.0 is vulnerable to XSS due to unsafe interpolation of the session GET parameter. This allows a remote attacker to execute an XSS attack on the domain Synapse is hosted on, by...Show more
AuthRestServlet in Matrix Synapse before 1.21.0 is vulnerable to XSS due to unsafe interpolation of the session GET parameter. This allows a remote attacker to execute an XSS attack on the domain Synapse is hosted on, by supplying the victim user with a malicious URL to the /_matrix/client/r0/auth/*/fallback/web or /_matrix/client/unstable/auth/*/fallback/web Synapse endpoints.Show less
1Matrix
1Synapse
Jun 17, 2026
Nov 8, 2019
N/A· v4
9.8 CRITICAL· v3
7.5 HIGH· v2
Matrix Synapse before 1.5.0 mishandles signature checking on some federation APIs. Events sent over /send_join, /send_leave, and /invite may not be correctly signed, or may not come from the expected servers.
1Matrix
2Sydent
Synapse
Jun 17, 2026
May 9, 2019
N/A· v4
7.5 HIGH· v3
5.0 MEDIUM· v2
An issue was discovered in Matrix Sydent before 1.0.3 and Synapse before 0.99.3.1. Random number generation is mishandled, which makes it easier for attackers to predict a Sydent authentication token or a Synapse random...Show more
An issue was discovered in Matrix Sydent before 1.0.3 and Synapse before 0.99.3.1. Random number generation is mishandled, which makes it easier for attackers to predict a Sydent authentication token or a Synapse random ID.Show less
1Matrix
1Sydent
Jun 17, 2026
Apr 19, 2019
N/A· v4
5.9 MEDIUM· v3
4.3 MEDIUM· v2
util/emailutils.py in Matrix Sydent before 1.0.2 mishandles registration restrictions that are based on e-mail domain, if the allowed_local_3pids option is enabled. This occurs because of potentially unwanted behavior in...Show more
util/emailutils.py in Matrix Sydent before 1.0.2 mishandles registration restrictions that are based on e-mail domain, if the allowed_local_3pids option is enabled. This occurs because of potentially unwanted behavior in Python, in which an email.utils.parseaddr call on user@bad.example.net@good.example.com returns the user@bad.example.net substring.Show less
2Fedoraproject
Matrix
2Fedora
Synapse
Jun 17, 2026
Mar 21, 2019
N/A· v4
7.5 HIGH· v3
5.0 MEDIUM· v2
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.
2Debian
Matrix
2Debian Linux
Synapse
Nov 21, 2024
Sep 18, 2018
N/A· v4
8.8 HIGH· v3
6.5 MEDIUM· v2
Matrix Synapse before 0.33.3.1 allows remote attackers to spoof events and possibly have unspecified other impacts by leveraging improper transaction and event signature validation.
1Matrix
1Synapse
Nov 21, 2024
Jun 14, 2018
N/A· v4
7.5 HIGH· v3
5.0 MEDIUM· v2
In Synapse before 0.31.2, unauthorised users can hijack rooms when there is no m.room.power_levels event in force.
1Matrix
1Synapse
Nov 21, 2024
Jun 13, 2018
N/A· v4
7.5 HIGH· v3
5.0 MEDIUM· v2
The on_get_missing_events function in handlers/federation.py in Matrix Synapse before 0.31.1 has a security bug in the get_missing_events federation API where event visibility rules were not applied correctly.