CVE-2026-121491
📛 CVE Title
Fiber Admin 3.1.0 - 4.0.0 - Unauthenticated RCE via Host Header
Description
The Fiber Admin WordPress plugin before 4.0.1 does not validate or escape a request header before writing it into a PHP file it regenerates on an unprotected admin hook, allowing unauthenticated attackers to execute arbitrary code when its custom database error page is enabled and they win a race against an administrator saving its settings.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- WPScan
- CVSS severity
- —
- CVSS score
- —
- CVSS vector
- —
- Effective score
- no score available from CNA, NVD, or AI yet
- CWE(s)
-
CWE-94 Improper Control of Generation of Code ('Code Injection') - Reserved
- 2026-11-03
- Published
- 2026-11-07 06:00 UTC
- Last updated
- 2026-11-07 18:16 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/121xxx/CVE-2026-121491.json
AI-forensic CVSS estimate
Used only when a CVE has no official CVSS from its CNA or NVD. An LLM estimates the v3.1 base score from the description; a HIGH/CRITICAL estimate promotes the CVE to a Threat.
No AI estimate yet — it runs automatically once NVD has been checked, or click the button above.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-118943
EUVD enrichment is queued; refresh the page in a few seconds.
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| Unknown | Fiber Admin |
3.1.0 (affected)
|
— |
Vendor references (1)
References embedded in the original CVE record by the assigning CNA.
- https://wpscan.com/vulnerability/42b9773d-9c69-4435-be20-ae86f52b4608/ exploitvdb-entrytechnical-description
Web references (0)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
No web references attached yet.
Remediations (10)
-
web:blogs.oracle.com
For more information about the Critical Patch Update program, see the security vulnerability remediation practices page located on the Oracle Trust Center.
2026-11-08 11:37 UTC -
web:cvedatabase.com
Search and analyze CVE vulnerabilities with instant access to CVSS scores, affected products, and remediation guidance.
2026-11-08 11:37 UTC -
web:cyberupdates365.com
Track critical CVE vulnerabilities 2026 with verified enterprise patch guides. Fix zero-days across VMware, WordPress, Windows, and cloud infrastructure.
2026-11-08 11:37 UTC -
web:hub.ivanti.com
Customers can resolve these vulnerabilities by updating to Ivanti Neurons for ITSM 2025.4 (On-Premise), available in ILS. No action is required for customers using the cloud solution as the fix was applied to all cloud environments on 12 December 2025.
2026-11-08 11:37 UTC -
web:support.esri.com
This patch deals specifically with the issues listed below under Issues addressed with this patch . As part of the patch installation, the ArcGIS Server service is stopped and restarted. The restart may take several minutes depending on the number of services published on the ArcGIS Server site. This patch can be uninstalled as outlined in the Uninstalling this patch on Windows and Uninstalling ...
2026-11-08 11:37 UTC -
web:support.sap.com
On 13 th of October 2026 , SAP security patch day saw the release of 16 new security notes and 4 GitHub security advisories. There are 2 updates to previously released security notes.
2026-11-08 11:37 UTC -
web:vulners.com
CVE-2026-121491 🗓️ 06 Nov 2026 22:00:26 Reported by WPScan Type cve 🔗 web.nvd.nist.gov 👁 21 Views
2026-11-08 11:37 UTC -
web:www.aikido.dev
CVE remediation is fixing known flaws in the software you run. Why upgrading often fails, what remediation actually involves, and how backporting fixes it.
2026-11-08 11:37 UTC -
web:www.openhands.dev
Compare 8 automated vulnerability remediation tools for 2026 on fixes, prioritization, integrations, and deployment control.
2026-11-08 11:37 UTC -
web:www.oracle.com
Prior Critical Patch Update and Critical Security Patch Update advisories should be reviewed for information regarding earlier published security patches. Refer to Critical Patch Updates, Critical Security Patch Updates, Security Alerts and Bulletins for information about Oracle Security advisories.
2026-11-08 11:37 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-121491.json.
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"baseScore": 9,
"baseSeverity": "CRITICAL",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "NONE",
"scope": "CHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H",
"version": "3.1"
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"shortName": "CISA-ADP"
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"title": "CISA ADP Vulnrichment"
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"cna": {
"affected": [
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"defaultStatus": "unaffected",
"product": "Fiber Admin",
"vendor": "Unknown",
"versions": [
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"source": {
"discovery": "EXTERNAL"
},
"title": "Fiber Admin 3.1.0 - 4.0.0 - Unauthenticated RCE via Host Header",
"x_generator": {
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"datePublished": "2026-11-07T06:00:26.885Z",
"dateReserved": "2026-11-03T14:07:07.923Z",
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"state": "PUBLISHED"
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