What is CVE-2021-27635?

CVE-2021-27635 is a medium-severity vulnerability in SAP Netweaver Application Server For Java, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 6.5/10. Published 2021-06-09.

How severe is CVE-2021-27635?

Medium severity. CVSS v3 base score is 6.5 out of 10.

Is CVE-2021-27635 known to be exploited?

3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

XXE in SAP Netweaver Application Server For Java

CVE-2021-27635

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 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.

Vulnerability class: XXE (XML External Entity)

Published 2021-06-09 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:H.

EPSS exploit prediction

EPSS: 0.016 (74.7th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 75th percentile — 74.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.016 · newest: 0.016 · change: 0.000

Affected products

SAP Netweaver Application Server For Java — versions 7.20, 7.30, 7.31
SAP Se Netweaver As For Java — versions < 7.20, < 7.30, < 7.31

Weakness classification (CWE)

CWE-611 — Improper Restriction of XML External Entity Reference (XXE)

Public proof-of-concept exploits

References

wiki.scn.sap.com/wiki/pages/viewpage.action (Vendor Advisory)
launchpad.support.sap.com/ (Permissions Required, Vendor Advisory)
seclists.org/fulldisclosure/2021/Oct/28 (mailing-list, Patch, Mailing List, Third Party Advisory)
packetstormsecurity.com/files/164592/SAP-JAVA-NetWeaver-System-Connections-XML-… (Patch, VDB Entry, Third Party Advisory)

Frequently asked questions

What is CVE-2021-27635?: CVE-2021-27635 is a medium-severity vulnerability in SAP Netweaver Application Server For Java, classified under Improper Restriction of XML External Entity Reference (XXE). CVSS score: 6.5/10. Published 2021-06-09.
How severe is CVE-2021-27635?: Medium severity. CVSS v3 base score is 6.5 out of 10.
Is CVE-2021-27635 known to be exploited?: 3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.