CVE-2026-84649
HIGHCVE-2026-84649 is a high-severity (CVSS 8.8) Cross-Site Request Forgery (CSRF) vulnerability. O3 Security confirms whether CVE-2026-84649 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
In Stapler 1839.ved17667b_a_eb_5 through 2107.v8dfcb_e8ed317 (both inclusive), except 2088.2093.vd7c3e58008a_6, included in Jenkins 2.447 through 2.579 (both inclusive), LTS 2.452.1…
Description
In Stapler 1839.ved17667b_a_eb_5 through 2107.v8dfcb_e8ed317 (both inclusive), except 2088.2093.vd7c3e58008a_6, included in Jenkins 2.447 through 2.579 (both inclusive), LTS 2.452.1 through 2.568.2 (both inclusive), an HTTP endpoint serving dynamically generated JavaScript resources embeds the user's cross-site request forgery (CSRF) token (crumb) as a string literal, allowing attackers with control over a page hosted on the same site as Jenkins to obtain a valid crumb for the targeted user's session and perform actions on their behalf.
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of the affected component has shipped for CVE-2026-84649 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-84649 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-84649. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-84649 in your dependencies?
O3 detects CVE-2026-84649 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.