csirt@kutim:~/threat-intel/cve/CVE-2021-21378

Katalog CVE

CVSS 8.2 · High EPSS 1,7%

Kerentanan Improper Authentication pada envoyproxy envoy. Skor CVSS 3.1 8.2 (High) menurut NVD.

Deskripsi (NVD)

Envoy is a cloud-native high-performance edge/middle/service proxy. In Envoy version 1.17.0 an attacker can bypass authentication by presenting a JWT token with an issuer that is not in the provider list when Envoy's JWT Authentication filter is configured with the `allow_missing` requirement under `requires_any` due to a mistake in implementation. Envoy's JWT Authentication filter can be configured with the `allow_missing` requirement that will be satisfied if JWT is missing (JwtMissed error) and fail if JWT is presented or invalid. Due to a mistake in implementation, a JwtUnknownIssuer error was mistakenly converted to JwtMissed when `requires_any` was configured. So if `allow_missing` was configured under `requires_any`, an attacker can bypass authentication by presenting a JWT token with an issuer that is not in the provider list. Integrity may be impacted depending on configuration if the JWT token is used to protect against writes or modifications. This regression was introduced on 2020/11/12 in PR 13839 which fixed handling `allow_missing` under RequiresAny in a JwtRequirement (see issue 13458). The AnyVerifier aggregates the children verifiers' results into a final status where JwtMissing is the default error. However, a JwtUnknownIssuer was mistakenly treated the same as a JwtMissing error and the resulting final aggregation was the default JwtMissing. As a result, `allow_missing` would allow a JWT token with an unknown issuer status. This is fixed in version 1.17.1 by PR 15194. The fix works by preferring JwtUnknownIssuer over a JwtMissing error, fixing the accidental conversion and bypass with `allow_missing`. A user could detect whether a bypass occurred if they have Envoy logs enabled with debug verbosity. Users can enable component level debug logs for JWT. The JWT filter logs will indicate that there is a request with a JWT token and a failure that the JWT token is missing.

Rincian

Terbit di NVD
11 Maret 2021
Terakhir diubah
17 Juni 2026
Status NVD
Modified
CVSS 3.1
8.2 (High), sumber NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N · uraikan di kalkulator
Jenis kelemahan (CWE)
CWE-287: Improper Authentication
CWE-303: Incorrect Implementation of Authentication Algorithm
EPSS (30 hari)
1,7% peluang dieksploitasi; lebih tinggi dari 76,7% CVE lain

Produk dan versi terdampak

VendorProdukVersi terdampak
envoyproxy envoy Versi 1.17.0

> Data dari konfigurasi CPE di NVD.

Referensi dan perbaikan

Sumber: NVD · CVE.org · EPSS. Halaman ini disusun otomatis dari data tersebut; pembaruan terakhir 5 Okt 2026, 20:10 WITA. Kalau sistem di Perangkat Daerah memakai produk ini dan butuh bantuan, laporkan lewat kanal pelaporan.