CVE-2021-21307
High PUBLISHEDRemote Code Exploit in Lucee Admin
Not yet in CISA KEV
Recommended Action
Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
At a Glance
Lucee Server is a dynamic, Java based (JSR-223), tag and scripting language used for rapid web application development. In Lucee Admin before versions 5.3.7.47, 5.3.6.68 or 5.3.5.96 there is an unauthenticated remote code exploit. This is fixed in versions 5.3.7.47, 5.3.6.68 or 5.3.5.96. As a workaround, one can block access to the Lucee Administrator.
- CVE Published
- Feb 11, 2021
- Exploitation Reported
- Apr 22, 2025
- CVSS
- 8.6 High
- EPSS
- —
Affected Versions
| Vendor | Product | Version | Status |
|---|---|---|---|
| lucee |
Lucee
|
>= 5.3.5.0, < 5.3.5.96 |
Affected |
| lucee |
Lucee
|
>= 5.3.6.0, < 5.3.6.68 |
Affected |
| lucee |
Lucee
|
>= 5.3.7.0, < 5.3.7.47 |
Affected |
CVE References
- GitHub — lucee/Lucee github.com · CVE Record https://github.com/lucee/Lucee/security/advisories/GHSA-2xvv-723c-8p7r
- GitHub — lucee/Lucee github.com · CVE Record https://github.com/lucee/Lucee/commit/6208ab7c44c61d26c79e0b0af103828...
- dev.lucee.org/t/lucee-vulnerability-alert-november-2020/7643 dev.lucee.org · CVE Record https://dev.lucee.org/t/lucee-vulnerability-alert-november-2020/7643
- GitHub — httpvoid/writeups github.com · CVE Record https://github.com/httpvoid/writeups/blob/main/Apple-RCE.md
- portswigger.net/daily-swig/security-researchers-earn-50k-aft... portswigger.net · CVE Record https://portswigger.net/daily-swig/security-researchers-earn-50k-afte...
Show 2 more references
- ciacfug.org/blog/updating-lucee-as-part-of-a-vulnerabili... ciacfug.org · CVE Record http://ciacfug.org/blog/updating-lucee-as-part-of-a-vulnerability-ale...
- packetstormsecurity.com/files/163864/Lucee-Administrator-imgProcess.... packetstormsecurity.com · CVE Record http://packetstormsecurity.com/files/163864/Lucee-Administrator-imgPr...
Recommended Actions
- Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
- Check enrichment artifacts for scanner coverage and available PoCs before rolling remediation validation.
- Use the Pro API to automate enrichment, telemetry, and workflow delivery for VM, SOC, and CTI pipelines.
Known Exploited Vulnerability Sources
Catalogues that list this CVE as a known exploited vulnerability.
Per-source evidence links for KEV attestations are available through the KEVIntel Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| The Shadowserver First | 2025-04-22 00:00 UTC |
Scanner Artifacts
Nuclei and Metasploit references linked to this CVE.
| Scanner | Reference | Detected |
|---|---|---|
| Nuclei | https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2021/CVE-2021-21307.yaml | Apr 25, 2025 |
| Metasploit | https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/linux/http/lucee_admin_imgprocess_file_write.rb | Apr 28, 2025 |
Virtual Patch
Compensating WAF rules to help reduce exposure to this CVE. Rule content and deployable vendor exports are available with KEVIntel Enterprise.
KEVIntel does not currently have a virtual patch for this CVE. When available, KEVIntel virtual patches ship as deployable ModSecurity, Cloudflare, and AWS WAF rules.
Enterprise feature. Virtual patch rule content and deployable vendor exports (ModSecurity, Cloudflare, AWS WAF) are available to KEVIntel Enterprise users.
CVSS Scores
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N
Exploitation Status
Exploited in the wild
Recorded 2025-04-22 00:00:00 UTC · The Shadowserver
Proof of concept available
Recorded 2025-04-28 15:02:08 UTC · Nuclei Templates
Weaknesses (CWE)
-
Missing Authorization
Scanner Integrations
| Scanner | Reference | Detected |
|---|---|---|
| Metasploit | https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/linux/http/lucee_admin_imgprocess_file_write.rb | Apr 28, 2025 |
| Nuclei | https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2021/CVE-2021-21307.yaml | Apr 25, 2025 |
Potential Proof of Concepts
These PoCs are unverified and could contain malware. Use at your own risk.
nuclei · Created Unknown
Timeline
Key exploitation, disclosure, scanner coverage, and KEV attestation events for this CVE.
-
15:02 UTC about 1 year ago15:02 UTC · about 1 year ago
Metasploit module available
Exploit module available
-
15:02 UTC about 1 year ago15:02 UTC · about 1 year ago
Public PoC available
Public proof-of-concept code published
-
00:00 UTC about 1 year ago00:00 UTC · about 1 year ago
Nuclei template available
Scanner coverage available
-
00:00 UTC about 1 year ago00:00 UTC · about 1 year ago
Added to KEVIntel KEV Feed
High-confidence, third-party attested exploitation
-
18:20 UTC over 5 years ago18:20 UTC · over 5 years ago
CVE published
Vulnerability disclosed publicly
-
00:00 UTC over 5 years ago00:00 UTC · over 5 years ago
CVE ID reserved
Identifier reserved by the CNA
Automate This Intelligence with the Pro API
Confidence scoring, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
Pro API Example
GET /api/v2/pro/kevs/CVE-2021-21307
{
"cve_id": "CVE-2021-21307",
"title": "Remote Code Exploit in Lucee Admin",
"affected_vendor": "lucee",
"affected_product": "Lucee",
"affected_versions": [
{ "vendor": "...", "product": "...", "status": "affected", "display_label": "..." }
],
"confidence": "High",
"cvss_score": 8.6,
"epss_score": null,
"exploit_status": {
"exploited_in_the_wild": true,
"active_exploitation_observed": false
},
"sensor_telemetry": { "...": "Pro API fields" },
"proof_of_concepts": [ "..." ],
"scanner_integrations": [ "..." ]
}