CVE-2026-39980 | OpenCTI up to 6.9.4 safeEjs.ts special elements used in a template engine

VDB-356629 · CVE-2026-39980 · GCVE-0-2026-39980 OPENCTI UP TO 6.9.4 SAFEEJS.TS SPECIAL ELEMENTS USED IN A TEMPLATE ENGINE HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 6.8 $0-$5k 1.16+ Summaryinfo A vulnerability was found in OpenCTI up to 6.9.4. It has been rated as problematic. This impacts an unknown function of the file safeEjs.ts. This manipulation causes improper neutralization of special elements used in a template engine. The identification of this vulnerability is CVE-2026-39980. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is advised. Detailsinfo A vulnerability has been found in OpenCTI up to 6.9.4 and classified as problematic. Affected by this vulnerability is an unknown function of the file safeEjs.ts. The manipulation with an unknown input leads to a improper neutralization of special elements used in a template engine vulnerability. The CWE definition for the vulnerability is CWE-1336. The product uses a template engine to insert or process externally-influenced input, but it does not neutralize or incorrectly neutralizes special elements or syntax that can be interpreted as template expressions or other code directives when processed by the engine. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is: OpenCTI is an open source platform for managing cyber threat intelligence knowledge and observables. Prior to 6.9.5, the safeEjs.ts file does not properly sanitize EJS templates. Users with the Manage customization capability can run arbitrary JavaScript in the context of the OpenCTI platform process during notifier template execution. This vulnerability is fixed in 6.9.5. The advisory is shared at github.com. This vulnerability is known as CVE-2026-39980 since 04/08/2026. The exploitation appears to be easy. The attack can be launched remotely. Additional levels of successful authentication are needed for exploitation. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1221 for this issue. Upgrading to version 6.9.5 eliminates this vulnerability. Productinfo Name OpenCTI Version 6.9.0 6.9.1 6.9.2 6.9.3 6.9.4 CPE 2.3info 🔒 🔒 🔒 CPE 2.2info 🔒 🔒 🔒 CVSSv4info VulDB Vector: 🔒 VulDB Reliability: 🔍 CVSSv3info VulDB Meta Base Score: 6.9 VulDB Meta Temp Score: 6.8 VulDB Base Score: 4.7 VulDB Temp Score: 4.5 VulDB Vector: 🔒 VulDB Reliability: 🔍 CNA Base Score: 9.1 CNA Vector (GitHub_M): 🔒 CVSSv2info Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock VulDB Base Score: 🔒 VulDB Temp Score: 🔒 VulDB Reliability: 🔍 Exploitinginfo Class: Improper neutralization of special elements used in a template engine CWE: CWE-1336 / CWE-791 / CWE-790 CAPEC: 🔒 ATT&CK: 🔒 Physical: No Local: No Remote: Yes Availability: 🔒 Status: Not defined Price Prediction: 🔍 Current Price Estimation: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock Threat Intelligenceinfo Interest: 🔍 Active Actors: 🔍 Active APT Groups: 🔍 Countermeasuresinfo Recommended: Upgrade Status: 🔍 0-Day Time: 🔒 Upgrade: OpenCTI 6.9.5 Timelineinfo 04/08/2026 CVE reserved 04/09/2026 +1 days Advisory disclosed 04/09/2026 +0 days VulDB entry created 04/09/2026 +0 days VulDB entry last update Sourcesinfo Advisory: github.com Status: Confirmed CVE: CVE-2026-39980 (🔒) GCVE (CVE): GCVE-0-2026-39980 GCVE (VulDB): GCVE-100-356629 Entryinfo Created: 04/09/2026 19:44 Changes: 04/09/2026 19:44 (62) Complete: 🔍 Cache ID: 99:B08:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸