Fiber Admin Plugin up to 4.0.0 on WordPress code injection

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.0$0-$5k0.00+

Summaryinfo

A vulnerability identified as critical has been detected in Fiber Admin Plugin up to 4.0.0. This impacts an unknown function. Performing a manipulation results in code injection. This vulnerability is identified as CVE-2026-121491. The attack can be initiated remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Fiber Admin Plugin up to 4.0.0. This affects some unknown functionality. The manipulation with an unknown input leads to a code injection vulnerability. CWE is classifying the issue as CWE-94. The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

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.

The advisory is shared at wpscan.com. This vulnerability is uniquely identified as CVE-2026-121491 since 11/03/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1059 for this issue.

Upgrading to version 4.0.1 eliminates this vulnerability.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Code injection
CWE: CWE-94 / CWE-74 / CWE-707
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Fiber Admin Plugin 4.0.1

Timelineinfo

11/03/2026 CVE reserved
11/07/2026 +4 days Advisory disclosed
11/07/2026 +0 days VulDB entry created
11/07/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: wpscan.com
Status: Confirmed

CNA: WPScan
CVE: CVE-2026-121491 (🔒)

GCVE (CVE): GCVE-0-2026-121491
GCVE (VulDB): GCVE-100-432441

Entryinfo

Created: 11/07/2026 07:15
Changes: 11/07/2026 07:15 (54)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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