Formula injection bypass in EspoCRM CSV and XLSX export
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA.
Summary
EspoCRM before 9.3.9 is affected. Its CSV and XLSX export checks only the first byte of a cell, so a formula trigger preceded by whitespace or a control character is exported without the leading single-quote prefix (CWE-1236). An authenticated user with low privileges can store such a value, and when a privileged user opens the exported file and accepts spreadsheet security prompts, the spreadsheet may evaluate it as a formula, enabling outbound data disclosure and, with DDE enabled on legacy configurations, command execution.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Description from the CNA
EspoCRM is an open source customer relationship management application. Prior to 9.3.9, application/Espo/Tools/Export/Format/Csv/Processor.php, application/Espo/Tools/Export/Format/Xlsx/OpenSpoutProcessor.php, and application/Espo/Tools/Export/Format/Xlsx/PhpSpreadsheetProcessor.php inspect only the first byte in sanitizeCellValue(). An authenticated low-privileged user can store a free-text value whose formula trigger is preceded by whitespace or a control character, causing CSV or XLSX export to omit the leading single-quote formula-neutralization prefix. When a privileged user opens the exported file and accepts applicable spreadsheet security prompts, spreadsheet software can ignore the whitespace or control-character prefix and evaluate the cell as a formula, permitting outbound data disclosure and, on legacy configurations with DDE enabled, command execution. This issue is fixed in version 9.3.9.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- 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
Upgrade EspoCRM to version 9.3.9, which fixes this issue.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
- Fix · CNA espocrm (espocrm) Fixed in 9.3.9
Timeline
- 2026-10-16 Threatist record created from CVE-2026-55154
- 2026-10-16 Priority changed: MEDIUM → LOW
- 2026-10-16 CISA SSVC decision points changed
References
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-2026-26120 EspoCRM: Stored XSS via SVG attachment loading same-origin JavaScript CVSS 3.1MEDIUM 6.8
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences