CVE-2021-38163
CVE-2021-38163 is a security flaw in SAP NetWeaver, SAP’s platform for running business applications. Attackers can upload a file to SAP NetWeaver and make it run. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 9 Jun 2022.[1]
SAP NetWeaver is business software or equipment. Most families won’t have it, but attackers break into it to get inside companies, and from there to what those companies hold about their customers, patients and staff.
Description
CISA calls it an unrestricted file upload in SAP NetWeaver. In its words: “SAP NetWeaver contains a vulnerability that allows unrestricted file upload.”[1]
The CVE record adds: “SAP NetWeaver (Visual Composer 7.0 RT) versions - 7.30, 7.31, 7.40, 7.50, without restriction, an attacker authenticated as a non-administrative user can upload a malicious file over a network and trigger its processing, which is capable of running operating system commands with the privilege of the Java Server process. These commands can be used to read or modify any information on the server or shut the server down making it unavailable.”[2]
The underlying weakness is CWE-23, in MITRE’s list of common software weaknesses.
It scores 8.8 out of 10 on the Common Vulnerability Scoring System, which rates it high, scored by NVD using CVSS 3.1.[2]
Affected versions
NVD’s record doesn’t list version ranges for it. CISA names the product as SAP NetWeaver.
Most families won’t have SAP NetWeaver; it’s for whoever looks after IT at work.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 9 Jun 2022, 268 days after it was made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 30 Jun 2022 to fix it.[1]
FIRST’s Exploit Prediction Scoring System, which estimates how likely a flaw is to be used in attacks in the next 30 days from what it sees across the internet, puts it at 37%. That’s in the top 2% of the flaws it scores.[3]
CISA assesses it as not automatable: each attack takes some work.
CISA doesn’t say who was attacked, or how.
Fix
CISA’s required action: “Apply updates per vendor instructions.”[1]
- Check whether you use it.SAP NetWeaver is business software or equipment, so most families won’t have it. If you run a business, or work from home on company equipment, ask whoever looks after your IT.
- Send this page to your IT person.Ask them to confirm it’s fixed, or not in use. CISA gave US government agencies until 30 Jun 2022 to fix it.
- If it can’t be fixed, take it offline.CISA’s advice when there’s no fix is to stop using the product, or take it off the internet, until there is one.
You can’t fix someone else’s server, but you can watch for what follows a break-in like this: a breach notice, a password reset you didn’t ask for, or a scam message that knows things it shouldn’t. HARD watches for those for you and your family.
Timeline
| Date | Event |
|---|---|
| The flaw is made public in the National Vulnerability Database, with a severity score of 8.8.[2] | |
| CISA adds it to its catalog of flaws known to be used in attacks.[1] | |
| CISA’s deadline for US government agencies to fix it.[1] | |
| FIRST puts the odds of it being used in attacks in the next 30 days at 37%.[3] |
See also
Other SAP NetWeaver flaws
- CVE-2025-42999: deserialization ·
- CVE-2025-31324: unrestricted file upload ·
- CVE-2017-12637: directory traversal ·
- CVE-2016-2388: information disclosure ·
- CVE-2016-2386: SQL injection ·
- CVE-2020-6287: missing authentication for critical function ·
Other SAP flaws
- CVE-2019-0344, SAP Commerce Cloud: deserialization of untrusted data ·
- CVE-2022-22536, SAP products: HTTP request smuggling ·
- CVE-2020-6207, SAP Solution Manager: missing authentication for critical function ·
- CVE-2018-2380, SAP Customer Relationship Management (CRM): path traversal ·
Similar flaws
- CVE-2026-76519, Cisco Secure Email Gateway: relative path traversal ·
- CVE-2026-34926, Trend Micro Apex One: (on-premise) directory traversal ·
- CVE-2024-27199, JetBrains TeamCity: relative path traversal ·
- CVE-2025-64446, Fortinet FortiWeb: path traversal ·
- CVE-2022-37042, Synacor Zimbra Collaboration Suite (ZCS): authentication bypass ·
Added the same day
- CVE-2016-2388, SAP NetWeaver: information disclosure ·
- CVE-2016-2386, SAP NetWeaver: SQL injection ·
Every SAP flaw on CISA’s list · Everything added in June 2022
References
- ^ Cybersecurity and Infrastructure Security Agency. “SAP NetWeaver Unrestricted File Upload Vulnerability”. Known Exploited Vulnerabilities Catalog, added 9 Jun 2022.
- ^ National Institute of Standards and Technology. “CVE-2021-38163 Detail”. National Vulnerability Database, published 14 Sep 2021.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.369, percentile 98.5, 31 Oct 2026.
- CVE Program. “CVE-2021-38163”. The official CVE record.
This article is built from CISA’s catalog (version 2026.10.30), NVD’s record and FIRST’s scores, kept in HARD’s database and checked every morning. The plain English is HARD’s.