CVE-2020-15840
MEDIUMCVE-2020-15840 is a medium-severity (CVSS 5.3) vulnerability in com.liferay.portal:com.liferay.portal.impl. O3 Security confirms whether CVE-2020-15840 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Liferay Portal and Liferay DXP Bypass via Double Encoded URL
Blast Radius
com.liferay.portal:com.liferay.portal.impl☕com.liferay.portal:release.dxp.bom☕com.liferay.portal:release.dxp.bom☕com.liferay.portal:release.dxp.bom☕com.liferay.portal:release.portal.bom☕com.liferay.portal:com.liferay.portal.implReal-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
In Liferay Portal before 7.3.1, Liferay Portal 6.2 EE, and Liferay DXP 7.2, DXP 7.1 and DXP 7.0, the property 'portlet.resource.id.banned.paths.regexp' can be bypassed with doubled encoded URLs.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | com.liferay.portal:com.liferay.portal.impl | ≥ 7.2.0&&< 7.4.0 | 7.4.0 |
| ☕Maven | com.liferay.portal:release.dxp.bom | all versions | 7.0.10.fp93 |
| ☕Maven | com.liferay.portal:release.dxp.bom | ≥ 7.1.0&&< 7.1.10.fp19 | 7.1.10.fp19 |
| ☕Maven | com.liferay.portal:release.dxp.bom | ≥ 7.2.0&&< 7.2.10.fp7 | 7.2.10.fp7 |
| ☕Maven | com.liferay.portal:release.portal.bom | all versions | 7.3.1 |
| ☕Maven | com.liferay.portal:com.liferay.portal.impl | all versions | 7.1.3 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for com.liferay.portal:com.liferay.portal.impl. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update com.liferay.portal:com.liferay.portal.impl to 7.4.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-15840 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 O3 protects you
O3 pinpoints whether CVE-2020-15840 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2020-15840. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2020-15840 in your dependencies?
O3 detects CVE-2020-15840 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.