CVE-2026-47775

mediumpriority · track · 0OT risk · elevatedEPSS 0.002 · 12 %ileDEEUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
0.22% (12th) EPSS
CVSS 6.8 · medium
Is it mine?
22 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · osv · cert_bund

EPSS · scored 2026-10-27

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.

01

cvss

Technical severity, 0–10. One row per scoring source.

6.8
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.16.8mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:Nsecondary · ENISA EU
v3.16.8mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:Nsecondary · security-advisories@github.comexploitability 1.6 · impact 5.2
v3.16.2mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: no · Technical Impact: totalcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-209USCWE-327US
04

affected products (22)

Products and version ranges known to be affected.

showing 20 of 22
05

advisories (2)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2026-2048Google Cloud Service Mesh und Envoy Proxy: Mehrere SchwachstellenDeutsch2026-06-23csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in Google Cloud Service Mesh und Envoy Proxy ausnutzen, um einen Denial-of-Service-Zustand zu verursachen, Sicherheitsmaßnahmen zu umgehen, vertrauliche Informationen offenzulegen oder andere, nicht näher bezeichnete Angriffe durchzuführen.

  • BIT-envoy-2026-47775Envoy OAuth2 Filter: Padding Oracle via AES-256-CBC Cookie Decryption2026-06-30vendor · osvUS

    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.

06

also known as (3)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

cnnvdenisa_euvdosvcert_bundnvdNVDCVE.orgMITRE
published 2026-06-26modified 2026-10-25
08

references (3)

External citations — patches, advisories, analysis.

scry

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