CVE-2021-22959

llhttp: HTTP Request Smuggling due to spaces in headers

Severity Score

6.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

The parser in accepts requests with a space (SP) right after the header name before the colon. This can lead to HTTP Request Smuggling (HRS) in llhttp < v2.1.4 and < v6.0.6.

El parser en acepta peticiones con un espacio (SP) justo después del nombre del encabezado antes de los dos puntos. Esto puede conllevar a un contrabando de peticiones HTTP (HRS) en llhttp versiones anteriores a v2.1.4 y versiones anteriores a v6.0.6

An HTTP Request Smuggling (HRS) vulnerability was found in the llhttp library, used by Node.JS. Spaces as part of the header names were accepted as valid. In situations where HTTP conversations are being proxied (such as proxy, reverse-proxy, load-balancer), an attacker can use this flaw to inject arbitrary messages through the proxy. The highest threat from this vulnerability is to confidentiality and integrity.

*Credits: N/A

CVSS Scores

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

Low

Availability

None

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Attack Vector

Network

Attack Complexity

Low

Authentication

None

Confidentiality

Partial

Integrity

Partial

Availability

None

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2021-01-06 CVE Reserved
2021-11-15 CVE Published
2024-07-31 EPSS Updated
2024-08-03 CVE Updated
2024-08-03 First Exploit
---------- Exploited in Wild
---------- KEV Due Date

CWE

CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

CAPEC

References (5)

URL	Tag	Source

URL	Date	SRC
https://hackerone.com/reports/1238709	2024-08-03

URL	Date	SRC
https://www.oracle.com/security-alerts/cpujan2022.html	2022-12-09

URL	Date	SRC
https://www.debian.org/security/2022/dsa-5170	2022-12-09
https://access.redhat.com/security/cve/CVE-2021-22959	2022-06-06
https://bugzilla.redhat.com/show_bug.cgi?id=2014057	2022-06-06

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Llhttp Search vendor "Llhttp"		Llhttp Search vendor "Llhttp" for product "Llhttp"				< 2.1.4 Search vendor "Llhttp" for product "Llhttp" and version " < 2.1.4"		node.js		Affected
Llhttp Search vendor "Llhttp"		Llhttp Search vendor "Llhttp" for product "Llhttp"				>= 3.0.0 < 6.0.6 Search vendor "Llhttp" for product "Llhttp" and version " >= 3.0.0 < 6.0.6"		node.js		Affected
Oracle Search vendor "Oracle"		Graalvm Search vendor "Oracle" for product "Graalvm"				20.3.4 Search vendor "Oracle" for product "Graalvm" and version "20.3.4"		enterprise		Affected
Oracle Search vendor "Oracle"		Graalvm Search vendor "Oracle" for product "Graalvm"				21.3.0 Search vendor "Oracle" for product "Graalvm" and version "21.3.0"		enterprise		Affected
Debian Search vendor "Debian"		Debian Linux Search vendor "Debian" for product "Debian Linux"				11.0 Search vendor "Debian" for product "Debian Linux" and version "11.0"		-		Affected