CVE-2021-27603Network attack vector

Service exhaustion via caller-controlled RFC wait

Published Apr 13, 2021 · Updated Aug 3, 2024

Denial of service in SAP NetWeaver AS ABAP 731, 740, and 750 allows remote authenticated users to interrupt service through RFC calls. The SPI_WAIT_MILLIS function module accepts a caller-selected duration and holds one ABAP work process for that entire interval. Low-privileged RFC access is required; parallel calls can occupy every work process and make the SAP system and hosted business applications unavailable.

CVSS severity6.5
Medium
EPSS probability0.86%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in SAP NetWeaver AS ABAP 731, 740, and 750 allows remote authenticated users to interrupt service through RFC calls. The SPI_WAIT_MILLIS function module accepts a caller-selected duration and holds one ABAP work process for that entire interval. Low-privileged RFC access is required; parallel calls can occupy every work process and make the SAP system and hosted business applications unavailable.

The record

CVE
CVE-2021-27603
Published
Apr 13, 2021
Updated
Aug 3, 2024
Vendor
SAP SE
Product
SAP NetWeaver AS for ABAP and ABAP Platform
Classifications
CWE-770, T1499.003
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 13, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=< 731
  2. Affected versionversion=< 740
  3. Affected versionversion=< 750

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

SAP SE · SAP NetWeaver AS for ABAP and ABAP Platformversion=< 731; version=< 740; version=< 750

Published CVSS scores

6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
4.0NIST NVDAV:N/AC:L/Au:S/C:N/I:N/A:P
6.5SAP SECVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-770Allocation of Resources Without Limits or Throttling
T1499.003Application Exhaustion Flood

Public exploit references

No public exploit references are available in this record.

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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