Security readout for executives and security teams
Plain-English summary
This SAP NetWeaver RFC Gateway flaw can let an unauthenticated network attacker crash the affected service. The documented impact is outage only: sources say attackers cannot view or modify data. Business urgency depends on whether affected SAP kernels are reachable by untrusted networks and how critical SAP availability is to operations.
Executive priority
Treat as high priority for SAP systems supporting critical business processes, especially if RFC Gateway is broadly reachable. The main risk is operational disruption, not confirmed data compromise.
Technical view
CVE-2021-27597 affects SAP NetWeaver AS for ABAP RFC Gateway across listed SAP kernel families. A specially crafted network packet triggers improper input validation in memmove(), causing an internal error and crash. CVSS 3.0 is 7.5 with network, low-complexity, no-privilege, no-user-interaction availability impact only.
Likely exposure
Exposure is likely where SAP NetWeaver AS for ABAP RFC Gateway runs the listed KRNL32NUC, KRNL64NUC, KRNL64UC, or KERNEL versions and is network-reachable. Internet or broad internal reachability materially raises denial-of-service risk.
Exploitation context
The provided bundle does not show CISA KEV listing or public active exploitation evidence. The vulnerability is remotely reachable and unauthenticated, but the cited impact is service crash, not data theft or modification.
Researcher notes
Evidence supports a network-triggered unauthenticated denial-of-service condition tied to improper input validation and CWE-125. The source bundle does not provide exploit details, indicators, or fixed version mapping beyond the SAP note reference.
Mitigation direction
- Review SAP Note 3020209 for vendor remediation and applicability.
- Apply SAP-supported kernel or RFC Gateway updates if directed by SAP.
- Confirm affected RFC Gateway services are not exposed beyond required networks.
- Prioritize availability monitoring for critical SAP systems until remediated.
Validation and detection
- Inventory SAP NetWeaver AS for ABAP RFC Gateway kernel family and version.
- Compare installed versions against the affected versions in the CVE record.
- Check whether RFC Gateway is reachable from untrusted or broad internal networks.
- Verify SAP Note 3020209 status and implemented remediation evidence.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-125: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2021-27597 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.5 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H3.93.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
7.5HighVector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://wiki.scn.sap.com/wiki/pages/viewpage.action?pageId=578125999CVE reference
- https://launchpad.support.sap.com/#/notes/3020209CVE reference
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Out-of-bounds Read
Out-of-bounds Read represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.