Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2021-43824— Null pointer dereference in envoy

Quick assessment

Affected
envoyproxy envoy
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Envoy是一款开源的分布式代理服务器。 Envoy 存在代码问题漏洞，该漏洞源于在受影响的版本中，当CONNECT请求被发送到配置了regex匹配的JWT过滤器时，精心设计的请求会崩溃。

CVSS 7.5 · High EPSS 1.06% · P63

Possible ATT&CK Techniques 1 AI

T1499 · Endpoint Denial of Service
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2021-43824

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Null pointer dereference in envoy
Source: CVE Program / CVE List V5
Vulnerability Description
Envoy is an open source edge and service proxy, designed for cloud-native applications. In affected versions a crafted request crashes Envoy when a CONNECT request is sent to JWT filter configured with regex match. This provides a denial of service attack vector. The only workaround is to not use regex in the JWT filter. Users are advised to upgrade.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
空指针解引用
Source: CVE Program / CVE List V5
Vulnerability Title
Envoy 代码问题漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Envoy是一款开源的分布式代理服务器。 Envoy 存在代码问题漏洞，该漏洞源于在受影响的版本中，当CONNECT请求被发送到配置了regex匹配的JWT过滤器时，精心设计的请求会崩溃。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
envoyproxy envoy >= 1.20.0, < 1.20.2 -

II. Public POCs for CVE-2021-43824

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2021-43824

请登录查看更多情报信息。

Patches & Fixes for CVE-2021-43824 (1)

Vendor Advisories for CVE-2021-43824 (1)

Same Patch Batch · envoyproxy · 2022-02-22 · 8 CVEs total

CVE-2021-43826 7.5 HIGH Crash when tunneling TCP over HTTP in Envoy
CVE-2022-21655 7.5 HIGH Incorrect handling of internal redirects results in crash in Envoy
CVE-2022-21654 7.4 HIGH Incorrect configuration handling allows TLS session re-use without re-validation in Envoy
CVE-2022-21656 7.4 HIGH X.509 subjectAltName matching bypass in Envoy
CVE-2022-21657 6.8 MEDIUM X.509 Extended Key Usage and Trust Purposes bypass in Envoy
CVE-2021-43825 6.1 MEDIUM Use-after-free in Envoy
CVE-2022-23606 4.4 MEDIUM Crash when a cluster is deleted in Envoy

IV. Related Vulnerabilities

Same product: envoy
Same vendor: envoyproxy
Same weakness: CWE-476

V. Comments for CVE-2021-43824

No comments yet

Leave a comment