Skip to main content

Envoy CVE-2024-32475

HIGH
Incorrect Check of Function Return Value (CWE-253)
2024-04-18 security-advisories@github.com
7.5
CVSS 3.1 · Vendor: github
View

Vulnerability Assessment

Weakness
CWE
ASVS 5.0
V16 - Security Logging and Error Handling Incorrect check of return value
Impact

CVSS score of 7.5 (HIGH). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required.

Exploit ScenarioDerived

This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the high-severity affected system.

This Week Schedule remediation this week. Why: HIGH severity (CVSS 7.0-8.9).
Patch available 0.7% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAI

Envoy is a cloud-native, open source edge and service proxy. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

This vulnerability is classified under CWE-253. Envoy is a cloud-native, open source edge and service proxy. When an upstream TLS cluster is used with auto_sni enabled, a request containing a host/:authority header longer than 255 characters triggers an abnormal termination of Envoy process. Envoy does not gracefully handle an error when setting SNI for outbound TLS connection. The error can occur when Envoy attempts to use the host/:authority header value longer than 255 characters as SNI for outbound TLS connection. SNI length is limited to 255 characters per the standard. Envoy always expects this operation to succeed and abnormally aborts the process when it fails. This vulnerability is fixed in 1.30.1, 1.29.4, 1.28.3, and 1.27.5. Affected products include: Envoyproxy Envoy.

Know when Envoy gets its next vulnerability

  • Watch products and get an email when something new is published
  • Check this CVE against your own stack and servers
  • Exploit and PoC references, threat intelligence from 22 sources

No credit card · 7-day full trial

Severity by source

Vendor (github) PRIMARY 7.5 HIGH
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Primary rating from Vendor (github) · only source for this CVE.

CVSS VectorVendor: github

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

DescriptionCVE.org

Envoy is a cloud-native, open source edge and service proxy. When an upstream TLS cluster is used with auto_sni enabled, a request containing a host/:authority header longer than 255 characters triggers an abnormal termination of Envoy process. Envoy does not gracefully handle an error when setting SNI for outbound TLS connection. The error can occur when Envoy attempts to use the host/:authority header value longer than 255 characters as SNI for outbound TLS connection. SNI length is limited to 255 characters per the standard. Envoy always expects this operation to succeed and abnormally aborts the process when it fails. This vulnerability is fixed in 1.30.1, 1.29.4, 1.28.3, and 1.27.5.

Threat Intelligence Overview

EPSS Score
0.7%
Top 52% exploitable
Data Quality
3 sources
Confidence: Low

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity HIGH
CISA KEV No
Public POC No
EPSS 0.7%
Patch available Yes
Active threat No
Deciding rule
HIGH severity (CVSS 7.0-8.9)
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived
Scheduled
Exploitation· derived
None
System Exposure· derived
Open
Automatable· derived
Yes
Human Impact· derived
Medium

Priority Score

39
Low Medium High Critical
KEV: 0
EPSS: +1
CVSS: +38
PoC: 0
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.

Affected Products (CPE)CVE.org

cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*
cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*
cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*
cpe:2.3:a:envoyproxy:envoy:1.30.0:*:*:*:*:*:*:*

More in Envoy

View all
CVE-2023-44487 HIGH POC
7.5 Oct 10

Denial of service against HTTP/2 server implementations allows remote unauthenticated attackers to exhaust server resour

CVE-2023-27488 CRITICAL POC
9.8 Apr 04

Envoy is an open source edge and service proxy designed for cloud-native applications. Rated critical severity (CVSS 9.8

CVE-2019-18802 CRITICAL POC
9.8 Dec 13

An issue was discovered in Envoy 1.12.0. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable,

CVE-2019-18801 CRITICAL POC
9.8 Dec 13

An issue was discovered in Envoy 1.12.0. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable,

CVE-2023-27493 CRITICAL POC
9.1 Apr 04

Envoy is an open source edge and service proxy designed for cloud-native applications. Rated critical severity (CVSS 9.1

CVE-2023-27491 CRITICAL POC
9.1 Apr 04

Envoy is an open source edge and service proxy designed for cloud-native applications. Rated critical severity (CVSS 9.1

CVE-2023-27487 CRITICAL POC
9.1 Apr 04

Envoy is an open source edge and service proxy designed for cloud-native applications. Rated critical severity (CVSS 9.1

CVE-2020-25017 HIGH POC
8.3 Oct 01

Envoy through 1.15.0 only considers the first value when multiple header values are present for some HTTP headers. Rated

CVE-2019-9900 HIGH POC
8.3 Apr 25

When parsing HTTP/1.x header values, Envoy 1.9.0 and before does not reject embedded zero characters (NUL, ASCII 0x0). R

CVE-2026-26308 HIGH POC
7.5 Mar 10

Envoy's RBAC filter improperly concatenates duplicate HTTP headers into comma-separated strings instead of validating ea

CVE-2024-53270 HIGH POC
7.5 Dec 18

Envoy is a cloud-native high-performance edge/middle/service proxy. Rated high severity (CVSS 7.5), this vulnerability i

CVE-2024-53269 HIGH POC
7.5 Dec 18

Envoy is a cloud-native high-performance edge/middle/service proxy. Rated high severity (CVSS 7.5), this vulnerability i

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy