`CVE-2020-13942` Apache Unomi

Affected software	Apache Unomi
Severity	9.8 Critical CVSS 3.1 2 scores
Fixed in	`1.5.2`
Weakness	Improper input validation (CWE-20)
Published	24 Nov 2020
Updated	17 Jun 2026

Description

It is possible to inject malicious OGNL or MVEL scripts into the /context.json public endpoint. This was partially fixed in 1.5.1 but a new attack vector was found. In Apache Unomi version 1.5.2 scripts are now completely filtered from the input. It is highly recommended to upgrade to the latest available version of the 1.5.x release to fix this problem.

CWE-74

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. 3 citations · honeypot sightings · 6 exploits · earliest 2021-04-12.
CISA Vulnrichment no assessment published
Indexed PoC 8 indexed Published artifacts you can open, in GitHub PoC, Nuclei; first seen 2020-11-18.
EPSS 69% chance in 30 days A model's forecast, not a report of exploitation. Higher than 99% of all scored CVEs.

VulnCheck KEV

Exploitation evidence from VulnCheck Known Exploited Vulnerabilities (VulnCheck KEV), used under VulnCheck's community terms. View CVE-2020-13942 in VulnCheck (free account), which lists 1 more exploit reference not shown here.

Evidence	Source	Detail	Date
Honeypot sighting	Shadowserver honeypots	Exploitation attempts seen on 770 days	2023-11-22 to 2026-11-12
Honeypot sighting	VulnCheck canaries	Exploitation attempts seen on 40 days	2026-04-30 to 2026-11-12
Reported exploitation	unit42.paloaltonetworks.com	/network-attack-trends-winter-2020	2021-04-12
Reported exploitation	cujo.com	/the-sysrv-botnet-and-how-it-evolved	2021-09-22
Reported exploitation	botconf.eu	/wp-content/uploads/2022/05/Botconf2022-24-PalotayZsigovits.pdf	2022-04-27
Exploit reference	VulnCheck XDB 05247f160481	Exploit type: initial-access	2020-11-20
Exploit reference	VulnCheck XDB 465a48e5ddd5	Exploit type: initial-access	2020-11-21
Exploit reference	VulnCheck XDB ff091b790f50	Exploit type: initial-access	2020-11-24
Exploit reference	VulnCheck XDB 1ac7e5a40dd2	Exploit type: initial-access	2023-12-21
Exploit reference	VulnCheck XDB 66d89e00d424	Exploit type: initial-access	2025-04-02

Evidence

Source

Detail

Date

Honeypot sighting

Shadowserver honeypots

Exploitation attempts seen on 770 days

2023-11-22 to 2026-11-12

Honeypot sighting

VulnCheck canaries

Exploitation attempts seen on 40 days

2026-04-30 to 2026-11-12

Reported exploitation

unit42.paloaltonetworks.com

/network-attack-trends-winter-2020

2021-04-12

Reported exploitation

cujo.com

/the-sysrv-botnet-and-how-it-evolved

2021-09-22

Reported exploitation

botconf.eu

/wp-content/uploads/2022/05/Botconf2022-24-PalotayZsigovits.pdf

2022-04-27

Exploit reference

VulnCheck XDB 05247f160481

Exploit type: initial-access

2020-11-20

Exploit reference

VulnCheck XDB 465a48e5ddd5

Exploit type: initial-access

2020-11-21

Exploit reference

VulnCheck XDB ff091b790f50

Exploit type: initial-access

2020-11-24

Exploit reference

VulnCheck XDB 1ac7e5a40dd2

Exploit type: initial-access

2023-12-21

Exploit reference

VulnCheck XDB 66d89e00d424

Exploit type: initial-access

2025-04-02

4 of these are GitHub repositories with fewer than 5 stars. They are listed for reference and don't count toward the exploitation status above.

Index	Artifact	Stars	First seen
GitHub PoC	CVE-2020-13942 unauthenticated RCE POC through MVEL and OGNL injection	28	2020-11-19
GitHub PoC	CVE-2020-13942 POC + Automation Script	8	2020-11-20
GitHub PoC	lp008/CVE-2020-13942	6	2020-11-18
GitHub PoC	CVE-2020-13942 Apache Unomi 远程代码执行漏洞脚getshell	4	2020-12-22
GitHub PoC	blackmarketer/CVE-2020-13942	3	2020-11-21
GitHub PoC	Vulhub unomi/CVE-2020-13942: Apache Unomi MVEL/OGNL Injection RCE (CVE-2020-13942), run with Isoloom		2026-10-08
GitHub PoC	Apache Unomi CVE-2020-13942: RCE Vulnerabilities		2021-01-11
Nuclei	Apache Unomi <1.5.2 - Remote Code Execution

Waratek protection

Mitigation candidate

A kind of vulnerability Waratek's rules address, with exploit code published or exploitation reported. No rule exists and none is planned yet. The decision below says what we found to build a rule from.

Protection none
Action unverified
Review automated Inferred
Record active

Decided by	The affected package being open source on Maven, so the fix can be read
Finding	This CVE affects an open-source Java library published on Maven Central (Maven packages: org.apache.unomi:unomi), so it is squarely in ARMR's territory and the source needed to understand the defect is public. That makes it a candidate for an ARMR patch rule. No rule exists and none is scheduled: the diff between the affected and fixed versions has not been read, and a closer look may find no hook point ARMR can act on.

Decided by

The affected package being open source on Maven, so the fix can be read

Finding

This CVE affects an open-source Java library published on Maven Central (Maven packages: org.apache.unomi:unomi), so it is squarely in ARMR's territory and the source needed to understand the defect is public. That makes it a candidate for an ARMR patch rule. No rule exists and none is scheduled: the diff between the affected and fixed versions has not been read, and a closer look may find no hook point ARMR can act on.

CVSS

9.8 CRITICAL v3.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H 2 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 9.8 CRITICAL CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H NVD Primary published

CVSS 2.0 7.5 none AV:N/AC:L/Au:N/C:P/I:P/A:P NVD Primary

Version	Score	Band	Vector	Assigner	Type
CVSS 3.1	9.8	CRITICAL	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`	NVD	Primary	published
CVSS 2.0	7.5	none	`AV:N/AC:L/Au:N/C:P/I:P/A:P`	NVD	Primary

Affected software and releases

Maven packages

Affected and fixed versions, from OSV.dev

Package Introduced Fixed Last affected

org.apache.unomi:unomi 0 1.5.2 unbounded

Package	Introduced	Fixed	Last affected
`org.apache.unomi:unomi`	0	`1.5.2`	unbounded

Products and versions

2 products, 2 version entries

Source	Vendor	Product	Scheme	Affected versions
nvd	apache	unomi	generic	≥ 1.5.0 and ＜ 1.5.2
osv	org.apache.unomi	unomi	generic	＜ 1.5.2

Source

Vendor

Product

Scheme

Affected versions

nvd

apache

unomi

generic

≥ 1.5.0 and ＜ 1.5.2

osv

org.apache.unomi

unomi

generic

＜ 1.5.2

References

URL	Tags
https://advisory.checkmarx.net/advisory/CX-2020-4284	WEB
https://lists.apache.org/thread.html/r08a4057ff7196b8880117edaa4b6207cbd36ed692d8dd1f5a56b4d0f@%3Cannounce.apache.org%3E	WEB
https://lists.apache.org/thread.html/r4a8fa91836687eaca42b5420a778ca8c8fd3a3740e4cf4401acc9118@%3Cdev.unomi.apache.org%3E	WEB
https://lists.apache.org/thread.html/r4a8fa91836687eaca42b5420a778ca8c8fd3a3740e4cf4401acc9118@%3Cusers.unomi.apache.org%3E	WEB
https://lists.apache.org/thread.html/r79672c25e0ef9bb4b9148376281200a8e61c6d5ef5bb705e9a363460@%3Ccommits.unomi.apache.org%3E	WEB
https://lists.apache.org/thread.html/rcb6d2eafcf15def433aaddfa06738e5faa5060cef2647769e178999a@%3Cdev.unomi.apache.org%3E	WEB
https://lists.apache.org/thread.html/rcb6d2eafcf15def433aaddfa06738e5faa5060cef2647769e178999a@%3Cusers.unomi.apache.org%3E	WEB
http://unomi.apache.org./security/cve-2020-13942.txt	WEB
http://www.openwall.com/lists/oss-security/2020/11/24/5	WEB
https://lists.apache.org/thread.html/r08a4057ff7196b8880117edaa4b6207cbd36ed692d8dd1f5a56b4d0f%40%3Cannounce.apache.org%3E

URL

Timeline

Published	2020-11-24	By the CVE Program.
VulnCheck KEV: earliest evidence	2021-04-12	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	2026-11-12	Date of the newest report, exploit reference or honeypot sighting in VulnCheck KEV's record.

Published

2020-11-24

By the CVE Program.

VulnCheck KEV: earliest evidence

2021-04-12

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

2026-11-12

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: org.apache.unomi:unomi

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 no match A reference pointing at the upstream fix: a commit, a PR, a Red Hat bug

18 open-source-maven decided it matched Mitigation candidate Open-source Maven artifact indexed by OSV (Maven packages: org.apache.unomi:unomi). The source is public, which makes an ARMR patch rule a candidate; nothing here establishes that one can be written.

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 no match A vulnerability class already blocked by an ARMR 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 no match Severity is CRITICAL — only MEDIUM/LOW are deprioritized

24 no-exploit-published no match A CISA or VulnCheck KEV listing, a CISA verdict of active exploitation, a reviewed exploit catalogue, or a GitHub PoC with 5 or more stars carries this CVE — exploit code is in use or published, so it stays a candidate

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

apache unomi not tracked cpe:2.3:a:apache:unomi:*:*:*:*:*:*:*:*

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