GHSA-9jhm-8m8c-c3f4 — medium GitHub Advisory (CVE-2021-29431) in pip/matrix-sydent

Description

Impact

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.

Patches

Fixed in 9e57334, 8936925, 3d531ed, 0f00412

Workarounds

A potential workaround would be to use a firewall to ensure that Sydent cannot reach internal HTTP resources.

For more information

If you have any questions or comments about this advisory, email us at [email protected].

Basic information

Type: reviewed
Severity: medium
Advisory on GitHub: Open advisory ↗
Repository advisory: Open repository advisory ↗
Source code: Browse source ↗
Published (advisory): 2021-04-19 14:54:15 UTC
Updated: 2024-09-30 20:40:51 UTC
GitHub reviewed: 2021-04-15 21:00:29 UTC
NVD published: 2021-04-15

Score	Percentile
0.30%	53.50%

CVSS Scores

Base score	Version	Severity	Vector
7.7	3.1	—	`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:L) A normal user session is enough; they don’t have to be admin. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:C) Breaking this can reach past the original component and bite other resources—bigger blast radius. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:N) Service keeps running; no real outage angle.
6.3	4.0	—	`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:H/SI:N/SA:N` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network. Attack complexity (AC:L) Exploitation conditions are straightforward and stable. Attack requirements (AT:N) No additional preconditions are required beyond normal reachability. Privileges required (PR:L) Low privileges are required. User interaction (UI:N) No user interaction is required. Vulnerable system confidentiality impact (VC:N) No confidentiality impact on the vulnerable system. Vulnerable system integrity impact (VI:N) No integrity impact on the vulnerable system. Vulnerable system availability impact (VA:N) No availability impact on the vulnerable system. Subsequent system confidentiality impact (SC:H) High confidentiality impact on subsequent systems. Subsequent system integrity impact (SI:N) No integrity impact on subsequent systems. Subsequent system availability impact (SA:N) No availability impact on subsequent systems.

Identifiers

Type	Value
GHSA	GHSA-9jhm-8m8c-c3f4 ↗
CVE	CVE-2021-29431 ↗

CWEs

CWE id	Name
CWE-20	Improper Input Validation
CWE-918	Server-Side Request Forgery (SSRF)

Affected packages (1)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem	Package	Vulnerable range	First patched	Vulnerable functions
pip	matrix-sydent	< 2.3.0	2.3.0	—

SSRF in Sydent due to missing validation of hostnames