CVE-2021-29432— Malicious users could control the content of invitation emails
Quick assessment
Affected
matrix-org sydent
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
Matrix Sydent是英国Matrix.org基金会的一款Matrix身份验证服务器API的实现。 Sydent 存在安全漏洞，攻击者可利用该漏洞从Sydent电子邮件地址发送任意电子邮件。
Possible ATT&CK Techniques 1 AI
T1534.001
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I. Basic Information for CVE-2021-29432
Vulnerability Information
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Vulnerability Title
Malicious users could control the content of invitation emails
Source: CVE Program / CVE List V5
Vulnerability Description
Sydent is a reference matrix identity server. 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. This issue has been fixed in 4469d1d.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Source: CVE Program / CVE List V5
Vulnerability Type
输入验证不恰当
Source: CVE Program / CVE List V5
Vulnerability Title
Matrix Sydent 输入验证错误漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Matrix Sydent是英国Matrix.org基金会的一款Matrix身份验证服务器API的实现。 Sydent 存在安全漏洞，攻击者可利用该漏洞从Sydent电子邮件地址发送任意电子邮件。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
| Vendor | Product | Affected Versions | CPE | Subscribe |
|---|---|---|---|---|
| matrix-org | sydent | < 2.3.0 | - |
|
II. Public POCs for CVE-2021-29432
| # | POC Description | Source Link | Shenlong Link |
|---|
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Patches & Fixes for CVE-2021-29432 (1)
Vendor Advisories for CVE-2021-29432 (1)
-
https://github.com/matrix-org/sydent/security/advisories/GHSA-mh74-4m5g-fcjx x_refsource_CONFIRM
Other References for CVE-2021-29432 (2)
-
https://pypi.org/project/matrix-sydent/ x_refsource_MISC
-
https://github.com/matrix-org/sydent/releases/tag/v2.3.0 x_refsource_MISC
Same Patch Batch · matrix-org · 2021-04-15 · 4 CVEs total
| CVE-2021-29431 | 7.7 HIGH | SSRF in Sydent due to missing validation of hostnames |
| CVE-2021-29430 | 7.5 HIGH | Denial of service attack via memory exhaustion |
| CVE-2021-29433 | 4.3 MEDIUM | Denial of service (via resource exhaustion) due to improper input validation |
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V. Comments for CVE-2021-29432
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