`CVE-2021-21479` SCIMono

Affected software	SCIMono
Severity	9.1 Critical CVSS 3.1 3 scores
Fixed in	`0.0.19`
Weakness	Command injection (CWE-77)
Published	9 Feb 2021
Updated	17 Jun 2026

Description

In SCIMono before 0.0.19, it is possible for an attacker to inject and execute java expression compromising the availability and integrity of the system.

CWE-74CWE-59CWE-62CWE-690CWE-917 · Expression language injection

Exploitation status

Exploited

Real-world exploitation reported by VulnCheck KEV. CISA has not confirmed it.

CISA KEV not listed
VulnCheck KEV listed Exploitation reported in the wild. 1 citation · honeypot sightings · earliest 2023-11-30.
CISA Vulnrichment no assessment published
Indexed PoC 1 indexed Published artifacts you can open, in Nuclei.
EPSS 10% chance in 30 days A model's forecast, not a report of exploitation. Higher than 96% of all scored CVEs.

VulnCheck KEV

Exploitation evidence from VulnCheck Known Exploited Vulnerabilities (VulnCheck KEV), used under VulnCheck's community terms. View CVE-2021-21479 in VulnCheck (free account).

Evidence	Source	Detail	Date
Honeypot sighting	Shadowserver honeypots	Exploitation attempts seen on 542 days	2023-11-30 to 2026-11-11
Honeypot sighting	VulnCheck canaries	Exploitation attempts seen on 26 days	2025-10-31 to 2026-11-03
Reported exploitation	app.crowdsec.net	/cti/cve-explorer/CVE-2021-21479	2025-06-07

Evidence

Source

Detail

Date

Honeypot sighting

Shadowserver honeypots

Exploitation attempts seen on 542 days

2023-11-30 to 2026-11-11

Honeypot sighting

VulnCheck canaries

Exploitation attempts seen on 26 days

2025-10-31 to 2026-11-03

Reported exploitation

app.crowdsec.net

/cti/cve-explorer/CVE-2021-21479

2025-06-07

Index	Artifact	Stars	First seen
Nuclei	SCIMono <0.0.19 - Remote Code Execution

Index

Artifact

Stars

First seen

Nuclei

SCIMono <0.0.19 - Remote Code Execution

Waratek protection

Protected by Waratek

Waratek has a rule that blocks attacks on this vulnerability.

Protection full Process
Action available security rule
Review automated Inferred
Record active

Decided by	A vulnerability class already blocked by an ARMR security rule
Finding	Protected by Waratek's ARMR command-injection security rule, which blocks this class of attack at the JVM level without a rule written for this CVE specifically. The CVE's weakness is CWE-77: Command Injection.
Candidate fix	https://github.com/SAP/scimono/security/advisories/GHSA-29q4-gxjq-rx5c : the maintainers' own security advisory: names the version that fixes it, so the fix is the difference between two releases

Decided by

A vulnerability class already blocked by an ARMR security rule

Finding

Protected by Waratek's ARMR command-injection security rule, which blocks this class of attack at the JVM level without a rule written for this CVE specifically. The CVE's weakness is CWE-77: Command Injection.

Candidate fix

https://github.com/SAP/scimono/security/advisories/GHSA-29q4-gxjq-rx5c : the maintainers' own security advisory: names the version that fixes it, so the fix is the difference between two releases

How to mitigate CVE-2021-21479

Upgrade SCIMono to 0.0.19 or later. Until you can, Waratek RASP blocks exploitation with its process rule. It runs inside the Java application, with no code changes.

Waratek RASP Runtime protection for Java applications

CVSS

9.1 CRITICAL v3.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H 3 metrics

We show the highest score from the newest CVSS version. Scores from different versions can't be compared, and the first score listed is sometimes a 0.0 placeholder.

Version Score Band Vector Assigner Type

CVSS 3.1 9.1 CRITICAL CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H NVD Primary published

CVSS 3.0 8.1 HIGH CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H cna@sap.com Secondary

CVSS 2.0 6.4 none AV:N/AC:L/Au:N/C:N/I:P/A:P NVD Primary

Version	Score	Band	Vector	Assigner	Type
CVSS 3.1	9.1	CRITICAL	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H`	NVD	Primary	published
CVSS 3.0	8.1	HIGH	`CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H`	cna@sap.com	Secondary
CVSS 2.0	6.4	none	`AV:N/AC:L/Au:N/C:N/I:P/A:P`	NVD	Primary

Affected software and releases

Maven packages

Affected and fixed versions, from OSV.dev

Package Introduced Fixed Last affected

com.sap.scimono:scimono-server 0 0.0.19 unbounded

Package	Introduced	Fixed	Last affected
`com.sap.scimono:scimono-server`	0	`0.0.19`	unbounded

Products and versions

2 products, 2 version entries

Source	Vendor	Product	Scheme	Affected versions
osv	com.sap.scimono	scimono-server	generic	＜ 0.0.19
nvd	sap	scimono	generic	＜ 0.0.19

Source

Vendor

Product

Scheme

Affected versions

osv

com.sap.scimono

scimono-server

generic

＜ 0.0.19

nvd

sap

scimono

generic

＜ 0.0.19

References

URL	Tags
https://github.com/SAP/scimono/security/advisories/GHSA-29q4-gxjq-rx5c	advisory
https://github.com/SAP/scimono/commit/413b5d75fa94e77876af0e47be76475a23745b80	WEB
https://mvnrepository.com/artifact/com.sap.scimono/scimono-server/0.0.19	WEB

URL

Timeline

Published	2021-02-09	By the CVE Program.
VulnCheck KEV: earliest evidence	2023-11-30	Date of the oldest evidence of exploitation in VulnCheck KEV's record. VulnCheck does not publish the date it listed the CVE.
NVD record modified	2026-06-17	NVD's own last-modified date for this record.
VulnCheck KEV: latest evidence	2026-11-11	Date of the newest report, exploit reference or honeypot sighting in VulnCheck KEV's record.

Published

2021-02-09

By the CVE Program.

VulnCheck KEV: earliest evidence

2023-11-30

Date of the oldest evidence of exploitation in VulnCheck KEV's record. VulnCheck does not publish the date it listed the CVE.

NVD record modified

2026-06-17

NVD's own last-modified date for this record.

VulnCheck KEV: latest evidence

2026-11-11

Date of the newest report, exploit reference or honeypot sighting in VulnCheck KEV's record.

How VRT decided (17 of 24 rules ran)

17 of 24 rules ran. The rest didn't run because an earlier rule had already settled the CVE.

# Rule Outcome Status Detail

identity: Does this identifier describe a vulnerability at all? the first rule that matches decides

1 rejected no match CVE Program withdrawal of this identifier

scope: Is it a vulnerability Waratek protects? the first rule that matches decides

2 armr-patch-file no match An ARMR patch file on disk for this CVE

3 armr-secure-rule-file no match An ARMR security-rule template on disk for this CVE

4 manual-classification no match A researcher's recorded decision for this specific CVE

5 manual classification no match Manual classification of this CVE in the legacy dataset

6 non-java-upstream no match A root cause in non-Java code: an OS kernel, a C library, or a bundled runtime

7 oracle-component no match The defect being in a component of a tracked product the agent does not reach: JavaFX, the Java SE installer, the JInitiator browser plug-in, the native WebLogic proxy plug-in, or a native part of Oracle Application Server or Collaboration Suite (HTTP Server, Web Cache, Internet Directory, mail and calendar servers). Oracle gives these no CPE of their own and names them only in the description.

8 java-client-side no match Oracle's own risk-matrix note saying the CVE is reached only through untrusted code in the Java sandbox (applets, Web Start) or only through a client installation of Java, so a server running its own trusted code is not exposed

9 osv-maven matched In scope Maven packages: com.sap.scimono:scimono-server

10 cna-maven-package not reached An affected Maven artifact named by the CNA itself

11 known-cpe-product not reached An NVD CPE naming a product ARMR tracks

12 cna-cpe-product not reached A CPE the CNA published naming a tracked product. Oracle publishes these on advisory day, months before NVD.

13 oracle-advisory-family not reached A tracked product family named in Oracle's own risk matrix. CPE cannot carry a suite name, only a module.

14 cna-named-product not reached A tracked product named in words by the CVE's own CNA, on a record with no CPE yet. Apache and Eclipse publish these on advisory day, before NVD adds CPE data.

15 non-deployable-product not reached The only affected product being a sealed appliance image, where Java runs but no -javaagent can be attached

16 unmatched-product not reached No tracked product matched above, and none present at all

disposition: What do we do about one that is? every rule runs

17 patch-hint matched Mitigation candidate References include candidate fix URL (advisory tier): https://github.com/SAP/scimono/security/advisories/GHSA-29q4-gxjq-rx5c

18 open-source-maven skipped The affected package being open source on Maven, so the fix can be read

19 poc-derivable skipped An indexed exploit clearing the evidence bar to reverse-engineer, where there is no source to read

20 no-exploit skipped Nothing to build a rule from yet: no published exploit, no CISA record of exploitation and no source-level change to read

21 secure-rule-match decided it matched Protected by Waratek CWE-77 (Command Injection) is mitigable by an ARMR command-injection security rule.

22 exploited-no-fix-or-poc skipped Somebody exploiting this CVE (a CISA or VulnCheck KEV listing, or a CISA verdict of active exploitation), with no fix, source code or PoC to build a rule from

23 below-action-threshold skipped Medium or Low severity, no CISA or VulnCheck KEV listing, no PoC clearing the evidence bar, no CISA verdict, no Oracle advisory

24 no-exploit-published skipped Exploit code for this candidate, published in a reviewed catalogue or a GitHub repository with 5 or more stars, or in use per CISA or VulnCheck; not only a CISA verdict, a forecast, or nothing at all

Products the scope rules checked

The products this CVE's record names, and whether VRT tracks each one. The scope rules decided on these.

Vendor Product Tracked CPE Source

sap scimono not tracked cpe:2.3:a:sap:scimono:*:*:*:*:*:*:*:*

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