Dashboard / CVE-2026-48743

CVE-2026-48743

HIGH
MEDIUM Priority: 0.02 BB Relevance: 65/100
Published: 2026-06-26 Modified: 2026-10-25 First seen: 2026-10-29 Status: active

Attack Surface

Network No Auth No Interaction Integ. Impact Scope Change

CVSS Vector Breakdown

AV: Network
AC: High
PR: None
UI: None
S: Changed
C: Low
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, Envoy can translate a downstream HTTP/3 request that is complete at the transport layer (HEADERS with FIN / headers-only close) but still carries a nonzero Content-Length into a complete upstream HTTP/1 request with unresolved body debt. In an HTTP/1 upstream deployment where the origin replies before reading the declared body and keeps the connection reusable, the beginning of the next Envoy-generated upstream request can be consumed as the first request's body. The remaining bytes are then parsed by the origin as a new HTTP/1 request. This was reproduced as a route-bypass/desync: direct /pwn was denied by Envoy, but the second downstream H3 stream received the response for backend-parsed GET /pwn HTTP/1.1. This vulnerability is fixed in 1.35.11, 1.36.7, 1.37.3, and 1.38.1.

Weakness Classification (1)

Affected Software (4)

VendorProductVersion
envoyproxy envoy 1.35.0 – 1.35.13
envoyproxy envoy 1.36.0 – 1.36.9
envoyproxy envoy 1.37.0 – 1.37.5
envoyproxy envoy 1.38.0 – 1.38.3

References & Advisories (1)

Bug Bounty Relevance

65 / 100
✓ Network accessible
✓ No authentication
✓ No user interaction

CVSS Score

7.5 / 10.0 v3.1
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:H/A:N

EPSS — Exploitation Probability

0.30%
Raw Score 0.002980
Percentile 22.5%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00298
2026-10-28
0.00298

Intelligence Sources

nvd ref →

External Links