Cyber Posture

CVE-2026-42261

High

Published: 08 May 2026

Published
08 May 2026
Modified
08 May 2026
KEV Added
Patch
CVSS Score 7.1 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:N
EPSS Score 0.0006 17.1th percentile
Risk Priority 14 60% EPSS · 20% KEV · 20% CVSS

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…

more

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.

Likely Mitigating ControlsAI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-20 CWE-693

Security testing and developer training directly verify and enforce proper input validation, reducing exploitability of injection and malformed-data weaknesses.

addresses: CWE-20 CWE-693

Security testing and evaluation at multiple SDLC stages directly detects missing or flawed input validation, with the required remediation process ensuring fixes are applied.

addresses: CWE-20 CWE-918

Directly implements checks on information inputs to reject invalid data before processing.

addresses: CWE-918 CWE-693

Detects server-side request forgery through monitoring of unexpected outbound connections.

addresses: CWE-20 CWE-693

Spam protection mechanisms perform filtering and detection on inbound/outbound messages, directly compensating for missing or weak input validation of unsolicited content.

addresses: CWE-693

Implements a reliable, tamperproof protection mechanism whose completeness can be assured.

addresses: CWE-693

Procedures for training on protection mechanisms reduce the chance of protection mechanism failures being present or exploitable.

addresses: CWE-693

Documented procedures to implement assessment, authorization, and monitoring controls prevent these protection mechanisms from failing due to undefined processes.

Security SummaryAI

Automated synthesis unavailable for this CVE.

Details

CWE(s)

AI Security AnalysisAI

AI Category
Other AI Platforms
Risk Domain
N/A
OWASP Top 10 for LLMs 2025
None mapped
MITRE ATLAS Techniques
None mapped
Classification Reason
Matched keywords: ai

References