CVE-2021-29430
published 2021-04-15CVE-2021-29430: 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…
PriorityP341high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
1.83%
76.5th percentile
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.
Affected
2 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| matrix-org | sydent | < 2.3.0 | 2.3.0 |
| matrix | sydent | < 2.3.0 | 2.3.0 |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P
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OSV
Sydent vulnerable to denial of service attack via memory exhaustion
osv·2021-04-19
CVE-2021-29430 [HIGH] Sydent vulnerable to denial of service attack via memory exhaustion
Sydent vulnerable to denial of service attack via memory exhaustion
### Impact
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 disk space 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.
### Patches
Patched by 89071a1, 0523511, f56eee3.
### Workarounds
Request sizes can be limited in an HTTP reverse-proxy.
There are no known workarounds for the problem with overlarge responses.
### For more information
GHSA
Sydent vulnerable to denial of service attack via memory exhaustion
ghsa·2021-04-19
CVE-2021-29430 [HIGH] CWE-20 Sydent vulnerable to denial of service attack via memory exhaustion
Sydent vulnerable to denial of service attack via memory exhaustion
### Impact
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 disk space 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.
### Patches
Patched by 89071a1, 0523511, f56eee3.
### Workarounds
Request sizes can be limited in an HTTP reverse-proxy.
There are no known workarounds for the problem with overlarge responses.
### For more information
OSV
CVE-2021-29430: Sydent is a reference Matrix identity server
osv·2021-04-15
CVE-2021-29430 CVE-2021-29430: Sydent is a reference Matrix identity server
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.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
https://github.com/matrix-org/sydent/commit/0523511d2fb40f2738f8a8549868f44b96e5dab7https://github.com/matrix-org/sydent/commit/89071a1a754c69a50deac89e6bb74002d4cda19dhttps://github.com/matrix-org/sydent/commit/f56eee315b6c44fdd9f6aa785cc2ec744a594428https://github.com/matrix-org/sydent/releases/tag/v2.3.0https://github.com/matrix-org/sydent/security/advisories/GHSA-wmg4-8cp2-hpg9https://pypi.org/project/matrix-sydent/https://github.com/matrix-org/sydent/commit/0523511d2fb40f2738f8a8549868f44b96e5dab7https://github.com/matrix-org/sydent/commit/89071a1a754c69a50deac89e6bb74002d4cda19dhttps://github.com/matrix-org/sydent/commit/f56eee315b6c44fdd9f6aa785cc2ec744a594428https://github.com/matrix-org/sydent/releases/tag/v2.3.0https://github.com/matrix-org/sydent/security/advisories/GHSA-wmg4-8cp2-hpg9https://pypi.org/project/matrix-sydent/
2021-04-15
Published