CVE-2026-33741 | EspoCRM: Stored XSS via SVG attachment loading same-origin JavaScript

EspoCRM is an open source customer relationship management application. Versions 9.3.3 and below allow authenticated users to upload SVG attachments through normal attachment-capable fields and later serve those SVG files as top-level inline documents through both the attachment and image entry points, resulting in stored cross-user XSS reachable through a normal attachment workflow. Although inline SVG script is blocked by the response CSP, the same CSP still allows same-origin external script. As a result, an attacker can upload a malicious SVG together with a second attacker-controlled JavaScript attachment, then trick another user into opening the SVG to execute JavaScript in the victim's EspoCRM origin. This issue has been fixed in version 9.3.4.

Published: 2026-05-19 Last update: 2026-05-20 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-33741 is rated Low Risk (31.4/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.04%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

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-2026-33741

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 2026-05-20 0.04%

Full EPSS history (1 record total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-33741

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.8 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:L/A:L 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: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:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
2.1 4.7 [email protected]

Weakness enumeration for CVE-2026-33741

Affected software / configurations for CVE-2026-33741

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-33741

cvelogic Threat Intelligence