#VU75156 Inconsistent interpretation of HTTP requests in SAP products - CVE-2021-33683

Vulnerability identifier: #VU75156

Vulnerability risk: Medium

CVSSv4.0: 1.2 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-33683

CWE-ID: CWE-444

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
SAP Web Dispatcher Kernel
Server applications / Application servers
SAP Web Dispatcher WEBDISP
Server applications / Other server solutions
Internet Communication Manager (ICM) KRNL32UC
Server applications / Other server solutions
Internet Communication Manager (ICM) KRNL64UC
Server applications / Other server solutions
Internet Communication Manager (ICM) KRNL64NUC
Server applications / Other server solutions
Internet Communication Manager (ICM) KRNL32NUC
Universal components / Libraries / Libraries used by multiple products

Vendor: SAP

Description

The vulnerability allows a remote attacker to perform HTTP request smuggling attacks.

The vulnerability exists due to improper validation of HTTP requests. A remote attacker can send a specially crafted HTTP request to the server and smuggle arbitrary HTTP headers.

Successful exploitation of vulnerability may allow an attacker to poison HTTP cache and perform phishing attacks.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

SAP Web Dispatcher Kernel: 7.21 - 7.83

SAP Web Dispatcher WEBDISP: 7.53 - 7.83

Internet Communication Manager (ICM) KRNL32UC: 7.21EXT - 7.22

Internet Communication Manager (ICM) KRNL64UC: 7.21EXT - 7.73

Internet Communication Manager (ICM) KRNL32NUC: 7.21EXT - 7.22

Internet Communication Manager (ICM) KRNL64NUC: 7.21EXT - 7.49

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External links
https://www.sap.com/documents/2022/02/fa865ea4-167e-0010-bca6-c68f7e60039b.html
https://launchpad.support.sap.com/#/notes/3000663

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.