CVE-2021-38162Public exploitNetwork attack vector

Request hijacking via conflicting HTTP length headers

Published Sep 14, 2021 · Updated Aug 4, 2024

HTTP request smuggling in affected SAP Web Dispatcher releases allows remote attackers to control requests forwarded to back-end servers. Web Dispatcher honors Transfer-Encoding while the downstream ICM honors Content-Length when both headers occur, leaving excess bytes to become the next request. Exploitation requires wdisp/HTTP/use_pool_for_new_conn to be enabled and can expose or alter user data, issue requests with victim credentials, or interrupt service.

CVSS severity8.9
High
EPSS probability2.74%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

HTTP request smuggling in affected SAP Web Dispatcher releases allows remote attackers to control requests forwarded to back-end servers. Web Dispatcher honors Transfer-Encoding while the downstream ICM honors Content-Length when both headers occur, leaving excess bytes to become the next request. Exploitation requires wdisp/HTTP/use_pool_for_new_conn to be enabled and can expose or alter user data, issue requests with victim credentials, or interrupt service.

The record

CVE
CVE-2021-38162
Published
Sep 14, 2021
Updated
Aug 4, 2024
Vendor
SAP SE
Product
SAP Web Dispatcher
Classifications
CWE-444, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 14, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=7.22EXT
  2. Affected versionversion=7.49
  3. Affected versionversion=7.53
  4. Affected versionversion=7.77
  5. Affected versionversion=7.81
  6. Affected versionversion=7.83
  7. Affected versionversion=KERNEL - 7.22
  8. Affected versionversion=KRNL64NUC - 7.22
  9. Affected versionversion=KRNL64UC -7.22
  10. Affected versionversion=WEBDISP - 7.49

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

SAP SE · SAP Web Dispatcherversion=7.22EXT; version=7.49; version=7.53; version=7.77; version=7.81; version=7.83; version=KERNEL - 7.22; version=KRNL64NUC - 7.22; version=KRNL64UC -7.22; version=WEBDISP - 7.49

Published CVSS scores

9.4NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L
7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P
8.9SAP SECVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-444Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
T1190Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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