Cyber Resilience

CVE-2021-27635

MediumPublic PoC

Published: 09 June 2021

Published
09 June 2021
Modified
21 November 2024
KEV Added
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Patch
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CVSS Score v3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:H
EPSS Score 0.0208 84.3th percentile
Risk Priority 14 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-27635 is a medium-severity Improper Restriction of XML External Entity Reference (CWE-611) vulnerability in Sap Netweaver Application Server For Java. Its CVSS base score is 6.5 (Medium).

Operationally, ranked in the top 15.7% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

SAP NetWeaver AS for JAVA, versions - 7.20, 7.30, 7.31, 7.40, 7.50, allows an attacker authenticated as an administrator to connect over a network and submit a specially crafted XML file in the application because of missing XML Validation, this…

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vulnerability enables attacker to fully compromise confidentiality by allowing them to read any file on the filesystem or fully compromise availability by causing the system to crash. The attack cannot be used to change any data so that there is no compromise as to integrity.

CWE(s)
CWE-611

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

sap
netweaver application server for java
7.20, 7.30, 7.31, 7.40, 7.50

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

CA-8 Penetration Testing
addresses: CWE-611

Penetration testing includes XML external entity payloads, detecting XXE vulnerabilities and enabling their mitigation.

SI-4 System Monitoring
addresses: CWE-611

Identifies XML external entity processing via monitoring of unusual file/network access or resource usage.

References