CVE-2026-50131

Published: Giu 11, 2026 Last Modified: Giu 11, 2026
ExploitDB:
Other exploit source:
Google Dorks:
HIGH 8,6
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: none
Scope: unchanged
Confidentiality: high
Integrity: low
Availability: low

Description

AI Translation Available

Fedify is a TypeScript library for building federated server apps powered by ActivityPub. Fedify previously addressed SSRF/internal network access in GHSA-p9cg-vqcc-grcx by adding public URL validation before runtime document and media fetching. However, the IPv4 validation logic present starting in version 0.11.2 and prior to versions 1.9.12, 1.10.11, 2.0.19, 2.1.15, and 2.2.4 appears incomplete. The `validatePublicUrl()` protection relies on `isValidPublicIPv4Address()` to reject non-public IPv4 destinations. The function blocks common private and local ranges such as `10.0.0.0/8`, `127.0.0.0/8`, `169.254.0.0/16`, `172.16.0.0/12`, and `192.168.0.0/16`, but it still treats several special-use, reserved, multicast, benchmarking, and carrier-grade NAT IPv4 ranges as valid public destinations. Because this validation is used as an SSRF defense before outbound fetches, this appears to be an incomplete mitigation or bypass class for the previous SSRF issue. Versions 1.9.12, 1.10.11, 2.0.19, 2.1.15, and 2.2.4 contain an updated patch.

EPSS (Exploit Prediction Scoring System)

Trend Analysis

EPSS (Exploit Prediction Scoring System)

Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.

EPSS Score
0,0006
Percentile
0,2th
Updated

EPSS Score Trend (Last 4 Days)

918

Server-Side Request Forgery (SSRF)

Incomplete
Abstraction: Base Structure: Simple
Common Consequences
Security Scopes Affected:
Confidentiality Integrity Access Control
Potential Impacts:
Read Application Data Execute Unauthorized Code Or Commands Bypass Protection Mechanism
Applicable Platforms
Technologies: Web Based, AI/ML, Web Server
View CWE Details
1286

Improper Validation of Syntactic Correctness of Input

Incomplete
Abstraction: Base Structure: Simple
Common Consequences
Security Scopes Affected:
Other
Potential Impacts:
Varies By Context
Applicable Platforms
All platforms may be affected
View CWE Details
1389

Incorrect Parsing of Numbers with Different Radices

Incomplete
Abstraction: Base Structure: Simple
Common Consequences
Security Scopes Affected:
Confidentiality Integrity
Potential Impacts:
Read Application Data Bypass Protection Mechanism Alter Execution Logic
Applicable Platforms
All platforms may be affected
View CWE Details
https://github.com/fedify-dev/fedify/security/advisories/GH…
https://github.com/fedify-dev/fedify/security/advisories/GHSA-xw9q-2mv6-9fr8
https://github.com/fedify-dev/fedify/security/advisories/GH…
https://github.com/fedify-dev/fedify/security/advisories/GHSA-xw9q-2mv6-9fr8