CVE-2026-21868

Katalog CVE

CVSS 7.5 · High EPSS 0,31%

Kerentanan Inefficient Regular Expression Complexity pada flagforge. Skor CVSS 3.1 7.5 (High) menurut github.com.

Deskripsi (NVD)

Flag Forge is a Capture The Flag (CTF) platform. Versions 2.3.2 and below have a Regular Expression Denial of Service (ReDoS) vulnerability in the user profile API endpoint (/api/user/[username]). The application constructs a regular expression dynamically using unescaped user input (the username parameter). An attacker can exploit this by sending a specially crafted username containing regex meta-characters (e.g., deeply nested groups or quantifiers), causing the MongoDB regex engine to consume excessive CPU resources. This can lead to Denial of Service for other users. The issue is fixed in version 2.3.3. To workaround this issue, implement a Web Application Firewall (WAF) rule to block requests containing regex meta-characters in the URL path.

Rincian

Terbit di NVD

8 Januari 2026

Terakhir diubah

17 Juni 2026

Status NVD

Analyzed

CVSS 3.1

7.5 (High), sumber github.com
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H · uraikan di kalkulator

Jenis kelemahan (CWE)

CWE-1333: Inefficient Regular Expression Complexity

EPSS (30 hari)

0,31% peluang dieksploitasi; lebih tinggi dari 22,3% CVE lain

Produk dan versi terdampak

> Data dari konfigurasi CPE di NVD.

Referensi dan perbaikan

• https://github.com/FlagForgeCTF/flagForge/security/advisories/GHSA-949h-9824-xmcx advisory vendor