Memory Corruption Vulnerability in SAP NetWeaver
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.
Affected components:
- 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)
Vulnerability Details
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.
Solution
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.
Report Timeline
- 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
REFERENCES
- Onapsis Blog Post:
https://onapsis.com/blog/sap-security-patch-day-june-2021-multiple-memory-corruption-vulnerabilities-can-lead-system - CVE Mitre:
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-27607
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-27628 - Vendor Patch:
https://launchpad.support.sap.com/#/notes/3021197
Advisory Information
- Public Release Date: 11/21/2021
- Security Advisory ID: ONAPSIS-2021-0015
- Vulnerability Submission ID: 867, 861
- Researcher(s): Yvan Genuer
Vulnerability Information
- 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
ABOUT OUR RESEARCH LABS
Onapsis Research Labs provides the industry analysis of key security issues that impact mission-critical systems and applications.
Delivering frequent and timely security and compliance advisories with associated risk levels, Onapsis Research Labs combine in-depth knowledge
and experience to deliver technical and business-context with sound security judgment to the broader information security community.
Find all reported vulnerabilities at https://github.com/Onapsis/vulnerability_advisories
This advisory is licensed under a Creative Commons 4.0 BY-ND International License
