CVE-2026-47775 — Security Box Score

CVE · referencelatest edition

Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-47775MEDIUM

envoyproxy envoy — Envoy OAuth2 Filter: Padding Oracle via AES-256-CBC Cookie Decryption

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   H   N   R  U  H  H  N    6.8   .0016    6.0     —

AFFECTED
  Product  Versions               Fixed
  envoy    >= 1.38.0, < 1.38.1 –  —

TIMELINE
  May 19  Reserved by GitHub_M
  Jun 26  EXPLOIT PUBLISHED — CVE-2026-47775 (envoyproxy envoy). Public exploit reference added.
  Jun 26  Published (CNA: GitHub_M)

CWE-209, CWE-327 · CNA: GitHub_M · CVSS v3.1 · 1 reference · NVD status: Analyzed

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.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
May 19, 2026	Reserved	Reserved by GitHub_M
June 26, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-47775 (envoyproxy envoy). Public exploit reference added.
June 26, 2026	Published	Published (CNA: GitHub_M)

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
envoyproxy	envoy	—	>= 1.38.0, < 1.38.1	—

Weaknesses

CWE-209 · CWE-327

References (1)

https://github.com/envoyproxy/envoy/security/advisories/GHSA-396h-jpq4-vc7p [Exploit, Vendor Advisory, Mitigation]

Authoritative record: CVE-2026-47775 at cve.org

Vendors: envoyproxy

Weaknesses: CWE-209 · CWE-327

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-47775 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.