BUFFALO WSR-300HP/WEX-G300 Web Form os command injection

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
8.2$0-$5k0.00

Summaryinfo

A vulnerability has been found in BUFFALO WSR-300HP and WEX-G300 and classified as very critical. This affects an unknown function of the component Web Form. This manipulation causes os command injection. This vulnerability is handled as CVE-2026-86530. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in BUFFALO WSR-300HP and WEX-G300 (the affected version unknown). It has been declared as very critical. Affected by this vulnerability is an unknown part of the component Web Form. The manipulation with an unknown input leads to a os command injection vulnerability. The CWE definition for the vulnerability is CWE-78. The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

BUFFALO Wi-Fi products handle some web form input improperly to assemble command line strings internally. An administrative user may send a crafted HTTP request and execute an arbitrary OS command.

The advisory is shared at buffalo.jp. This vulnerability is known as CVE-2026-86530 since 09/24/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation needs additional levels of successful authentication. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/28/2026). MITRE ATT&CK project uses the attack technique T1202 for this issue.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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

Productinfo

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License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 8.2
VulDB Meta Temp Score: 8.2

VulDB Base Score: 9.1
VulDB Temp Score: 9.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.2
CNA Vector (jpcert): 🔒

CVSSv2info

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

Exploitinginfo

Class: Os command injection
CWE: CWE-78 / CWE-77 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

09/24/2026 CVE reserved
09/28/2026 +4 days Advisory disclosed
09/28/2026 +0 days VulDB entry created
09/28/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: buffalo.jp
Status: Not defined

CVE: CVE-2026-86530 (🔒)
GCVE (CVE): GCVE-0-2026-86530
GCVE (VulDB): GCVE-100-411001

Entryinfo

Created: 09/28/2026 10:56
Changes: 09/28/2026 10:56 (72)
Complete: 🔍
Cache ID: 216::103

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

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