NetWeaver ABAP Server and ABAP Platform: Authentication Bypass by Capture-replay
CVE-2023-0014 is a critical-severity authentication bypass by capture-replay vulnerability in NetWeaver ABAP Server and ABAP Platform from SAP, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected NetWeaver ABAP Server and ABAP Platform versions: SAP_BASIS 701; SAP_BASIS 702; SAP_BASIS 710, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.74% chance of exploitation within 30 days, higher than 55% of scored CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of NetWeaver ABAP Server and ABAP Platform you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on launchpad.support.sap.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| SAP | NetWeaver ABAP Server and ABAP Platform | SAP_BASIS 701; SAP_BASIS 702; SAP_BASIS 710; SAP_BASIS 711; SAP_BASIS 730; SAP_BASIS 731; SAP_BASIS 740; SAP_BASIS 750; and 18 more ranges | Not stated |
| SAP | Netweaver Application Server Abap | 700; 701; 702; 710; 711; 730; 731; 740; and 8 more ranges | Not stated |
| SAP | Netweaver Application Server Abap Kernel | 7.22; 7.53; 7.77; 7.81; 7.85; 7.89 | Not stated |
| SAP | Netweaver Application Server Abap Krnl64nuc | 7.22; 7.22ext | Not stated |
| SAP | Netweaver Application Server Abap Krnl64uc | 7.22; 7.22ext; 7.53 | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 9.0 | Critical | CNA (sap.com) |
| CVSS 3.1 | 9.8 | Critical | NVD |
Official description
SAP NetWeaver ABAP Server and ABAP Platform - versions SAP_BASIS 700, 701, 702, 710, 711, 730, 731, 740, 750, 751, 752, 753, 754, 755, 756, 757, KERNEL 7.22, 7.53, 7.77, 7.81, 7.85, 7.89, KRNL64UC 7.22, 7.22EXT, 7.53, KRNL64NUC 7.22, 7.22EXT, creates information about system identity in an ambiguous format. This could lead to capture-replay vulnerability and may be exploited by malicious users to obtain illegitimate access to the system.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Authentication Bypass by Capture-replay
A capture-replay flaw exists when the design of the product makes it possible for a malicious user to sniff network traffic and bypass authentication by replaying it to the server in question to the same effect as the original message (or with minor changes).
How developers prevent this class of flaw
- Utilize some sequence or time stamping functionality along with a checksum which takes this into account in order to ensure that messages can be parsed only once.
- Since any attacker who can listen to traffic can see sequence numbers, it is necessary to sign messages with some kind of cryptography to ensure that sequence numbers are not simply doctored along with content.
More Authentication Bypass by Capture-replay vulnerabilities (CWE-294)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Recent Authentication Bypass by Capture-replay vulnerabilities
- 7.8 High severity
- 7.8 High severity
- 8.1 High severity
- 7.5 High severity
- 7.5 High severity
- 9.8 Critical severity
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