Dashboard / CVE-2026-47775

CVE-2026-47775

MEDIUM
MEDIUM Priority: 0.01 BB Relevance: 54/100
Published: 2026-06-26 Modified: 2026-10-25 First seen: 2026-10-29 Status: active

Attack Surface

Network No Auth Conf. Impact Integ. Impact

CVSS Vector Breakdown

AV: Network
AC: High
PR: None
UI: Required
S: Unchanged
C: High
I: High
A: None

Description

Envoy is an open source edge and service proxy designed for cloud-native applications. Prior to 1.35.11, 1.36.7, 1.37.3, and 1.38.1, the OAuth2 HTTP filter's encrypt()/decrypt() functions use AES-256-CBC without an authentication tag (no HMAC, no AEAD). The /callback endpoint returns HTTP 302 on successful decryption and HTTP 401 on padding failure, creating a padding oracle. An attacker who obtains the encrypted CodeVerifier cookie can recover the plaintext PKCE code_verifier in ~6,200 requests (~100 seconds), then exchange it with a stolen authorization code to obtain the victim's access token. This vulnerability is fixed in 1.35.11, 1.36.7, 1.37.3, and 1.38.1.

Weakness Classification (2)

Affected Software (4)

VendorProductVersion
envoyproxy envoy 1.35.0 – 1.35.11
envoyproxy envoy 1.36.0 – 1.36.7
envoyproxy envoy 1.37.0 – 1.37.3
envoyproxy envoy 1.38.0 – 1.38.1

References & Advisories (1)

Bug Bounty Relevance

54 / 100
✓ Network accessible
✓ No authentication

CVSS Score

6.8 / 10.0 v3.1
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N

EPSS — Exploitation Probability

0.22%
Raw Score 0.002190
Percentile 12.4%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00219
2026-10-28
0.00219

Intelligence Sources

nvd ref →

External Links