CVE-2021-3742 | Server-Side Request Forgery (SSRF) in chatwoot/chatwoot

A Server-Side Request Forgery (SSRF) vulnerability was discovered in chatwoot/chatwoot, affecting all versions prior to 2.5.0. The vulnerability allows an attacker to upload an SVG file containing a malicious SSRF payload. When the SVG file is used as an avatar and opened in a new tab, it can trigger the SSRF, potentially leading to host redirection.

Published: 2024-11-15 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-3742 is rated Moderate Risk (45.3/100): CVSS High severity, with low exploitation likelihood (EPSS 0.37%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-3742

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.16% 0.37% +0.20%
2 2026-04-06 0.13% 0.16% +0.04%
3 2025-11-21 0.13%

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-3742

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H 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:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 5.9 [email protected]
7.9 3.1 HIGH
CVSS:3.1/AV:A/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:A)
Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
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:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
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:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.2 6.0 134c704f-9b21-4f2e-91b3-4a467353bcc0
7.9 3.0 HIGH
CVSS:3.0/AV:A/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:A)
Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
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:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
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:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
1.2 6.0 [email protected]

Weakness enumeration for CVE-2021-3742

Affected software / configurations for CVE-2021-3742

Vendor Product Version Raw CPE
chatwoot chatwoot < 2.5.0 cpe:2.3:a:chatwoot:chatwoot:*:*:*:*:*:*:*:*

References for CVE-2021-3742

cvelogic Threat Intelligence