CVE-2026-35212: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in OpenCTI-Platform opencti
OpenCTI is an open source platform for managing cyber threat intelligence knowledge and observables. Versions prior to 7.260227.0 are vulnerable to XSS in the rendering of email-message observable body data. The content of the body field isn't appropriately sanitized when being rendered. Does require user interaction but could be exploited by someone sharing stix or any of the ingester. This could lead to CSRF and then large scale session theft. Version 7.260227.0 contains a fix.
AI Analysis
Technical Summary
CVE-2026-35212 is a CWE-79 (Improper Neutralization of Input During Web Page Generation) vulnerability affecting OpenCTI-Platform's opencti product. The issue occurs because the email-message observable body data is not properly sanitized before rendering, enabling cross-site scripting attacks. This can be exploited when a user interacts with maliciously crafted STIX or ingester data, potentially leading to CSRF and session theft. The vulnerability affects all versions prior to 7.260227.0, which contains the remediation.
Potential Impact
Successful exploitation of this vulnerability allows an attacker to execute arbitrary scripts in the context of the victim's browser when viewing the vulnerable content. This can lead to cross-site request forgery (CSRF) attacks and large-scale session theft, compromising user accounts and potentially the integrity of the threat intelligence platform data.
Mitigation Recommendations
A fix is available in OpenCTI-Platform opencti version 7.260227.0. Users should upgrade to this version or later to remediate the vulnerability. No additional vendor advisory is provided, so patch status beyond this version is not confirmed. Until upgrading, exercise caution when sharing or ingesting untrusted STIX or email-message observable data.
CVE-2026-35212: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in OpenCTI-Platform opencti
Description
OpenCTI is an open source platform for managing cyber threat intelligence knowledge and observables. Versions prior to 7.260227.0 are vulnerable to XSS in the rendering of email-message observable body data. The content of the body field isn't appropriately sanitized when being rendered. Does require user interaction but could be exploited by someone sharing stix or any of the ingester. This could lead to CSRF and then large scale session theft. Version 7.260227.0 contains a fix.
CVSS v4.0
Score 5.3medium
Affected software
pkg:github/opencti-platform/openctiRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-35212 is a CWE-79 (Improper Neutralization of Input During Web Page Generation) vulnerability affecting OpenCTI-Platform's opencti product. The issue occurs because the email-message observable body data is not properly sanitized before rendering, enabling cross-site scripting attacks. This can be exploited when a user interacts with maliciously crafted STIX or ingester data, potentially leading to CSRF and session theft. The vulnerability affects all versions prior to 7.260227.0, which contains the remediation.
Potential Impact
Successful exploitation of this vulnerability allows an attacker to execute arbitrary scripts in the context of the victim's browser when viewing the vulnerable content. This can lead to cross-site request forgery (CSRF) attacks and large-scale session theft, compromising user accounts and potentially the integrity of the threat intelligence platform data.
Mitigation Recommendations
A fix is available in OpenCTI-Platform opencti version 7.260227.0. Users should upgrade to this version or later to remediate the vulnerability. No additional vendor advisory is provided, so patch status beyond this version is not confirmed. Until upgrading, exercise caution when sharing or ingesting untrusted STIX or email-message observable data.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-01T18:48:58.937Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a1f4fb5e29bf47b5009becc
Added to database: 06/02/2026, 21:48:37 UTC
Last enriched: 06/10/2026, 11:09:28 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 76
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