CVE-2021-33683

CVE-2021-33683 is a medium-severity vulnerability in Sap Web Dispatcher with a CVSS 3.x base score of 4.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-444.

Key facts

Description

SAP Web Dispatcher and Internet Communication Manager (ICM), versions - KRNL32NUC 7.21, 7.21EXT, 7.22, 7.22EXT, KRNL32UC 7.21, 7.21EXT, 7.22, 7.22EXT, KRNL64NUC 7.21, 7.21EXT, 7.22, 7.22EXT, 7.49, KRNL64UC 7.21, 7.21EXT, 7.22, 7.22EXT, 7.49, 7.53, 7.73, WEBDISP 7.53, 7.73, 7.77, 7.81, 7.82, 7.83, KERNEL 7.21, 7.22, 7.49, 7.53, 7.73, 7.77, 7.81, 7.82, 7.83, process invalid HTTP header. The incorrect handling of the invalid Transfer-Encoding header in a particular manner leads to a possibility of HTTP Request Smuggling attack. An attacker could exploit this vulnerability to bypass web application firewall protection, divert sensitive data such as customer requests, session credentials, etc.

Frequently asked questions

What is CVE-2021-33683?
SAP Web Dispatcher and Internet Communication Manager (ICM), versions - KRNL32NUC 7.21, 7.21EXT, 7.22, 7.22EXT, KRNL32UC 7.21, 7.21EXT, 7.22, 7.22EXT, KRNL64NUC 7.21, 7.21EXT, 7.22, 7.22EXT, 7.49, KRNL64UC 7.21, 7.21EXT, 7.22, 7.22EXT, 7.49, 7.53, 7.73, WEBDISP 7.53, 7.73, 7.77, 7.81, 7.82, 7.83, KERNEL 7.21, 7.22, 7.49, 7.53, 7.73, 7.77, 7.81, 7.82, 7.83, process invalid HTTP header. The incorrect handling of the invalid Transfer-Encoding header in a particular manner leads to a possibility of HTTP Request Smuggling attack. An attacker could exploit this vulnerability to bypass web application firewall protection, divert sensitive data such as customer requests, session credentials, etc.
How severe is CVE-2021-33683?
CVE-2021-33683 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2021-33683 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33683?
CVE-2021-33683 primarily affects Sap Web Dispatcher. In total, 30 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-33683?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-33683 published?
CVE-2021-33683 was published on 2021-07-14 and last updated on 2026-06-17.

References

Affected products (30)

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