CVE-2026-78386
Fix: RansomLook/RansomLook@cc91829CVE-2026-78386 is a Information Exposure vulnerability. O3 Security confirms whether CVE-2026-78386 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
RansomLook exposed sensitive operator-side scraping configuration through multiple unauthenticated API responses. Location records associated with ransomware groups and markets were…
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-78386.
Description
RansomLook exposed sensitive operator-side scraping configuration through multiple unauthenticated API responses. Location records associated with ransomware groups and markets were returned largely verbatim to unauthenticated callers whenever the location itself was not marked as private.
These records could contain internal fields such as header, which may include authentication headers, session cookies, or other credentials used to access monitored websites; init_script, which may contain logic used to bypass CAPTCHA, anti-bot protections, or paywalls; and browser, which discloses details about the scraping environment.
An unauthenticated remote attacker could query the affected API endpoints and obtain these values. Leaked authentication material could potentially be replayed against the monitored service, while disclosure of scraping and bypass logic could allow site operators or other attackers to identify and defeat RansomLook's collection mechanisms.
The patch introduces an explicit allowlist of fields permitted in public location records and strips all operator-side fields before returning data to unauthenticated users.
The accompanying change from string:postname to path:postname appears to be a functional correction allowing legitimate post titles containing / and does not, based on this patch alone, represent the security issue.
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-2026-78386 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-2026-78386 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-2026-78386. 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-2026-78386 in your dependencies?
O3 detects CVE-2026-78386 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.