csirt@kutim:~/threat-intel/cve/CVE-2026-55165

Katalog CVE

CVSS 4.8 · Medium EPSS 0,15%

Kerentanan Improper Verification of Cryptographic Signature. Skor CVSS 3.1 4.8 (Medium) menurut github.com.

Deskripsi (NVD)

Lemur manages TLS certificate creation. Prior to 1.9.2, the JWT verifier in lemur/auth/service.py:130-137 used fetch_token_header to read header_data["alg"] from an unverified token and passed that attacker-controlled value to decode_with_multiple_secrets. PyJWT 2.x rejects alg=none with the configured key, so the flaw is a defense-in-depth gap rather than a direct authentication bypass in the shipped configuration. The unpinned algorithm can become exploitable after an asymmetric-signing migration through algorithm confusion, and it weakens algorithm-based anomaly detection because the token chooses the recorded value. A separate disclosure of LEMUR_TOKEN_SECRET would also permit forged HS256 tokens, although that disclosure is an independent prerequisite. The fix introduces the server-controlled LEMUR_TOKEN_ALGORITHMS allowlist and defaults it to HS256. This issue is fixed in version 1.9.2.

Rincian

Terbit di NVD
18 Agustus 2026
Terakhir diubah
8 September 2026
Status NVD
Deferred
CVSS 3.1
4.8 (Medium), sumber github.com
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N · uraikan di kalkulator
Jenis kelemahan (CWE)
CWE-347: Improper Verification of Cryptographic Signature
EPSS (30 hari)
0,15% peluang dieksploitasi; lebih tinggi dari 4,0% CVE lain

Produk dan versi terdampak

NVD belum mencantumkan data produk (CPE) untuk CVE ini. Produk yang terdampak biasanya disebut di deskripsi dan di advisory vendor pada daftar referensi.

Referensi dan perbaikan

Sumber: NVD · CVE.org · EPSS. Halaman ini disusun otomatis dari data tersebut; pembaruan terakhir 5 Okt 2026, 20:11 WITA. Kalau sistem di Perangkat Daerah memakai produk ini dan butuh bantuan, laporkan lewat kanal pelaporan.