Is CVE-2026-42261 actively exploited?

No active exploitation of CVE-2026-42261 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2026-42261 be exploited remotely?

Yes. CVE-2026-42261 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2026-42261?

CVE-2026-42261 has a CVSS score of 7.1 (HIGH).

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HIGH

CVE-2026-42261

CWE-20Published: May 8, 2026· Updated: May 12, 2026

7.1

CVSS v3.1

EPSS:0.06%probability of exploitation in 30 daysPercentile:17.2th

Official Description

PromptHub is an all-in-one AI toolbox for prompt, skill, and agent management. From version 0.4.9 to before version 0.5.4, apps/web/src/routes/skills.ts exposes an authenticated endpoint POST /api/skills/fetch-remote that fetches a user-supplied URL server-side and reflects the response body (up to 5 MB) back to the caller. The SSRF protection in apps/web/src/utils/remote-http.ts (isPrivateIPv6) attempts to block private/loopback destinations, but multiple alternate-but-valid IPv6 representations bypass the check. The bypasses reach any IPv4 address (loopback, RFC1918, link-local) via IPv4-mapped IPv6 in hex form, and the canonical ::1 via any representation that isn't the literal string "::1". Any authenticated user (role: user or admin) can trigger the SSRF. On deployments configured with ALLOW_REGISTRATION=true — a supported and documented configuration — this means any internet user who can register. This issue has been patched in version 0.5.4.

NVD Source

Technical Analysis

CVE-2026-42261 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in complete confidentiality breach (data exposure), with a CVSS base score of 7.1.