{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-76821 in the wild and no public exploit code.","fix":"No fix has been published for CVE-2026-76821 yet. Limit exposure of the affected software until one is available.","what":"CVE-2026-76821 is a high-severity denial of service vulnerability in OpenCTI-Platform opencti, published on 15 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-76821 and fix it if it is affected.\n\nWhat it is: CVE-2026-76821 is a high-severity denial of service vulnerability in OpenCTI-Platform opencti, published on 15 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-76821 in the wild and no public exploit code.\n\nAffected product: OpenCTI-Platform opencti. No package-level version data is available, so check the vendor advisory linked from the reference page.\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-76821/ (Markdown: https://insights.sbomify.com/CVE-2026-76821/index.md)","id":"CVE-2026-76821","markdown":"https://insights.sbomify.com/CVE-2026-76821/index.md","name":"CVE-2026-76821","record":{"aliases":["GHSA-7g3x-wc2m-9h9x"],"analysis":{"component_type":"web_application","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Threat Intelligence Platform","requires_auth":"low_privilege","summary":"An authenticated user can cause a denial of service in OpenCTI by submitting a malicious regular expression in the JSON ingestion mapper.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"GitHub_M","cpe":[],"cvss":{"score":7.1,"severity":"high","source":"cna","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","version":"4.0"},"cwes":[{"id":"CWE-400","name":"Uncontrolled Resource Consumption"},{"id":"CWE-1333","name":"Inefficient Regular Expression Complexity"}],"description":"OpenCTI is an open source platform for managing cyber threat intelligence knowledge and observables. Prior to 7.260706.0, the JSON ingestion mapper's extractWithRegexp formula function compiled a user-supplied regular expression with the JavaScript RegExp engine in opencti-platform/opencti-graphql/src/parser/json-mapper.ts without validating its complexity. An authenticated user with JSON mapper creation permission could provide a catastrophically backtracking pattern and matching ingestion input, blocking the Node.js event loop and making the GraphQL API unavailable to all users. Scheduled ingestion could repeatedly execute the malicious mapper without additional attacker action, and recovery could require disabling the mapper and restarting the process. The issue affects availability and does not expose or modify data. This issue is fixed in version 7.260706.0.","ecosystems":[],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":false,"headline":"OpenCTI: User-Controlled ReDoS in JSON Ingestion Mapper","id":"CVE-2026-76821","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"denial_of_service","year":"2026"},"n_packages":0,"n_references":4,"next":{"headline":"RestrictedPython: Sandbox escape via string.Formatter field resolution","id":"CVE-2026-76825"},"packages":[],"prev":{"headline":"OpenCTI: Synchronizer SSRF: stream fetch has no URL validation","id":"CVE-2026-76820"},"products":["opencti"],"published":"2026-09-15","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-09-16","vendors":["OpenCTI-Platform"]},"summary":"An authenticated user can cause a denial of service in OpenCTI by submitting a malicious regular expression in the JSON ingestion mapper.","url":"https://insights.sbomify.com/CVE-2026-76821/"}