Impact On Business
An unauthenticated attacker without specific knowledge of the system can send a specially crafted packet over a network which will trigger an internal error in the system causing the system to crash and rendering it unavailable.
Affected Components Description
The SAP dispatcher service is part of SAP Kernel. Mandatory, it manages, gathers and collects the requests from end users then forward them to work process.Without SAP dispatcher service, the SAP system is not able to process any users requests.
- SAP kernel 32 and 64 bits, unicode and non-unicode
- SAP KERNEL 7.22
- SAP KERNEL 7.22EXT
- SAP KERNEL 7.49
- SAP KERNEL 7.53
- SAP KERNEL 7.73
- SAP KERNEL 7.77
- SAP KERNEL 7.81
- SAP KERNEL 8.04
(Check SAP Note 3021197 for detailed information on affected releases)
CVE-2021-27607 : A NULL pointer dereference exist in ThSncIn(REQUEST_BUF**, unsigned char), where _Z10DpCaGetPtri tries to read a part of input controlled by an attacker, then return 0x0 instead of a pointer to normal value if the input is 0xffffffff.
CVE-2021-27628 : A memory corruption vulnerability exists for DpRTmPrepareReq(DP_SESSION_INFO) in Disp+work binary through the SAP Dispatcher service. If an attacker crafts a valid SAP Dispatcher packet, with valid header, but with a total packet size smaller than normal, the subtraction operation results in a negative value. Also if this negative value is anticipated and put in the same packet at a particular offset, the check operation that compares the two values will pass, and this value is used as size during the next operation.
SAP has released SAP Note 3021197 which provides patched versions of the affected components.
The patches can be downloaded from https://launchpad.support.sap.com/#/notes/3021197.
Onapsis strongly recommends SAP customers to download the related security fixes and apply them to the affected components in order to reduce business risks.
- 02/01/2021: Onapsis sends details to SAP
- 02/04/2021: SAP provides internal ID
- 02/08/2021: SAP confirms CVSS
- 06/09/2021: SAP releases SAP Note fixing the issue.
- 11/21/2021: Advisory published
- Onapsis Blog Post:
- CVE Mitre:
- Vendor Patch:
- Public Release Date: 11/21/2021
- Security Advisory ID: ONAPSIS-2021-0015
- Vulnerability Submission ID: 867, 861
- Researcher(s): Yvan Genuer
- Vendor: SAP
- Vulnerability Class: |LS|CWE-20|RS| Improper Input Validation, |LS|CWE-125|RS| Out-of-bounds Read, |LS|CWE-476|RS| NULL Pointer Dereference
- CVSS v3 score: 7.5 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Severity: High
- CVE: CVE-2021-27628, CVE-2021-27607
- Vendor patch Information: SAP Security Note 3021197
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Find all reported vulnerabilities at https://github.com/Onapsis/vulnerability_advisories
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