EspoCRM: Stored XSS via SVG attachment loading same-origin JavaScript
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Cross-site scripting
- Confidentiality · integrity · availability
- High · Low · Low
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-79.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
- Fix · CNA espocrm (espocrm) Fixed in 9.3.4
Timeline
- 2026-10-02 Threatist record created from CVE-2026-33741
More espocrm vulnerabilities
- TI-2020-19229 EspoCRM 5.7.0 < 5.9.0 - Two-Factor Authentication Bypass via Auth Token Reuse Between Accounts with Identical Passwords CVSS 4.0HIGH 8.6
- TI-2026-26036 Path traversal in espocrm CVSS 3.1CRITICAL 9.1
- TI-2025-32670 EspoCRM vulnerable to LDAP Injection through Improper Neutralization of Special Elements CVSS 3.1MEDIUM 6.5
- TI-2026-26112 EspoCRM has Admin TemplateManager path traversal that allows arbitrary file read write and delete CVSS 3.1HIGH 7.2
- TI-2025-23468 EspoCRM vulnerable to HTML Injection into phishing, which may lead to account takeover CVSS 4.0HIGH 7.0
- TI-2026-29769 EspoCRM: IDOR in EmailTemplate Prepare Endpoint Leaks Entity Data via Email Address Lookup CVSS 3.1MEDIUM 6.5
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences