How severe is CVE-2020-13942?

CVE-2020-13942 has a CVSS score of 9.8/10, rated CRITICAL. Immediate patching is strongly recommended.

Which packages are affected by CVE-2020-13942?

CVE-2020-13942 affects the following packages: org.apache.unomi:unomi (Maven). Ecosystems affected: Maven.

How do I fix CVE-2020-13942?

Update org.apache.unomi:unomi to 1.5.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-13942 is resolved across your whole dependency graph.

How do I detect CVE-2020-13942 in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.unomi:unomi, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2020-13942 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Is CVE-2020-13942 actively exploited in the wild?

Yes. There are 13 known exploit references for CVE-2020-13942, including 8 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2020-13942?

CVE-2020-13942 has an EPSS (Exploit Prediction Scoring System) score of 68.5%, placing it in the 99th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. A score above 50% indicates significantly elevated exploitation risk — immediate patching is strongly recommended.

What type of vulnerability is CVE-2020-13942?

CVE-2020-13942 is classified as Improper Input Validation (CWE-20), CWE-74 (CWE-74). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

Is there exploit tooling available for CVE-2020-13942?

A Nuclei detection template exists for CVE-2020-13942, meaning automated scanners can fingerprint it. Public exploit tooling significantly increases real-world risk — prioritize patching and ensure detection coverage. Exploit tooling should only ever be used in isolated, authorized testing environments.

When was CVE-2020-13942 published, and has it been updated?

CVE-2020-13942 was published on November 24, 2020 and was last updated on October 24, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

☕

☕ Maven

Not in CISA KEV

CRITICAL severity

CVE-2020-13942 — unomi

CRITICAL

CVE-2020-13942 is a critical-severity (CVSS 9.8) Improper Input Validation vulnerability in org.apache.unomi:unomi. 13 public exploit or proof-of-concept references are indexed, so weaponization risk is real. A fix is available for org.apache.unomi:unomi — see the affected versions and patch details below.

Injection and Improper Input Validation in Apache Unomi

Also known asGHSA-xp5j-wj4h-2jq9

Published

Nov 24, 2020

Updated

Oct 24, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

13 known

Exploitation data as of Nov 6, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

68.5%probability of exploitation in next 30 days

High Risk0.00%

Lower risk than most CVEs99th percentile — riskier than 99% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

1 pkg affected

☕org.apache.unomi:unomi

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.

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.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`org.apache.unomi:unomi`	all versions	1.5.2`org.apache.unomi:unomi:1.5.2`

Affected Products

1 product · 1 configurations

Application

unomiapache

≥ 1.5.0 && < 1.5.2

range

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

It is possible to inject malicious OGNL or MVEL scripts into the /contex…

advisory.checkmarx.netNVDMay 2021

Report on lists.apache.org

lists.apache.orgNVDMay 2021

Report on github.com

github.comGithubNov 2020

Report on github.com

github.comGithubNov 2020

Report on github.com

github.comGithubNov 2020

Report on github.com

github.comGithubDec 2020

Report on github.com

github.comGithubNov 2020

Report on github.com

github.comAPIDec 2020

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.unomi:unomi, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.apache.unomi:unomi to 1.5.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-13942 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How to detect CVE-2020-13942

A community-maintained Nuclei template exists for this CVE. You can scan for it directly:

nuclei -id cve-2020-13942 -u https://target

Template: Apache Unomi <1.5.2 - Remote Code Execution
Severity: critical
Impact: Successful exploitation of this vulnerability can allow an attacker to execute arbitrary code on the affected server.
Remediation: Apache Unomi users should upgrade to 1.5.2 or later.

Template by ProjectDiscovery nuclei-templates (dwisiswant0), MIT licensed. View the full template. Scan only systems you are authorised to test.

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2020-13942 in your dependencies?

Find it across Maven, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVE-2020-13942 — unomi

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

Description

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

How to detect CVE-2020-13942

Frequently Asked Questions

Is CVE-2020-13942 in your dependencies?