Summary
CVE-2026-78372 is a missing authorization vulnerability (CWE-862) in RansomLook, an open-source ransomware activity tracking and aggregation platform. The flaw allows unauthenticated, remote attackers to access private group, market, and ransom-note data — including names, note content, metadata, post counts, and uptime statistics — that the application is designed to restrict. The issue carries a CVSS v4.0 score of 9.2 (Critical), reflecting network exploitability with no authentication or privileges required and a high confidentiality impact.
Technical details
- Root cause: RansomLook does not consistently enforce authorization/privacy checks across its web views and API endpoints. Filtering logic that is supposed to exclude private groups, markets, and their associated ransom notes from public output is missing or incomplete in several code paths.
- Trigger conditions: No authentication is required. An attacker simply needs to know or guess a private group/market slug, or use the exposed
/comparefeature and search/API endpoints, to retrieve restricted data. - Attack vector: Network — exploitable remotely over HTTP against the RansomLook web application and its API.
- Impact:
- The
/compareendpoint permits direct querying of private entities, returning post counts and uptime data that should not be publicly visible. - Ransom-note detail views and search results can expose private group names, ransom-note content, and related metadata to unauthenticated users.
- API endpoints for group listing, recent notes, group-specific notes, and individual note retrieval could return data belonging to private groups/markets without an authorization check.
- Successful exploitation results in disclosure of confidential threat-intelligence data (e.g., ransomware group/market identities and note contents) that operators intended to keep private, which may undermine ongoing investigations or expose sensitive sourcing.
- The
Affected software
- Product: RansomLook (RansomLook/RansomLook on GitHub)
- Affected versions: All versions from the initial release through 2.0.0 (inclusive)
Severity
- CVSS v4.0 Base Score: 9.2 (Critical)
- Vector:
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N
Mitigation and recommended actions
- Immediate: Upgrade RansomLook to a version that includes the authorization fix (commit
dc92d6d5c076bcdbf3476aca42daf0260e8d99d7and later), which introduces centralized private-group/note slug filtering (get_private_group_slugs(),get_private_note_slugs(),note_is_private()) and enforces it across the/compareendpoint, note detail views, search, and the notes API. Confirm the running instance is on a patched release before considering it remediated. - If immediate patching is not possible:
- Restrict network access to self-hosted RansomLook instances (e.g., place behind authentication, VPN, or IP allow-listing) so that only trusted users can reach the web application and API.
- Audit any configured "private" groups/markets and review logs for unusual
/compare, search, or API requests referencing those group/market slugs. - Temporarily disable or restrict the
/comparefeature and public API endpoints if private groups are configured and patching cannot be applied promptly.

