1Panel-dev MaxKB up to 2.8.0 OSS File Service toctou

CVSS Meta Temp Score
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CTI Interest Score
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4.4$0-$5k0.00

Summaryinfo

A vulnerability was found in 1Panel-dev MaxKB up to 2.8.0. It has been rated as problematic. Affected by this vulnerability is an unknown functionality of the component OSS File Service. This manipulation causes toctou. This vulnerability is tracked as CVE-2026-42336. The attack is only possible within the local network. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability has been found in 1Panel-dev MaxKB up to 2.8.0 and classified as problematic. Affected by this vulnerability is an unknown function of the component OSS File Service. The manipulation with an unknown input leads to a toctou vulnerability. The CWE definition for the vulnerability is CWE-367. The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check. This can cause the product to perform invalid actions when the resource is in an unexpected state. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

MaxKB is an open-source AI assistant for enterprise. MaxKB 2.8.0 and prior are vulnerable to a server-side request forgery (SSRF) bypass in the OSS file service URL fetch functionality due to inconsistent DNS resolution between validation and actual request execution, allowing attackers to access internal network services. This vulnerability is fixed in 2.8.1.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2026-42336 since 04/26/2026. The exploitation appears to be difficult. The attack needs to approached within the local network. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 2.8.1 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-31989). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

Name

Version

Website

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: 4.6
VulDB Meta Temp Score: 4.4

VulDB Base Score: 4.6
VulDB Temp Score: 4.4
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: Toctou
CWE: CWE-367 / CWE-362
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: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: MaxKB 2.8.1

Timelineinfo

04/26/2026 CVE reserved
05/26/2026 +30 days Advisory disclosed
05/26/2026 +0 days VulDB entry created
05/27/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-6m4p-9wwc-4q5q
Status: Confirmed

CVE: CVE-2026-42336 (🔒)
GCVE (CVE): GCVE-0-2026-42336
GCVE (VulDB): GCVE-100-365827
EUVD: 🔒

Entryinfo

Created: 05/26/2026 23:37
Updated: 05/27/2026 01:38
Changes: 05/26/2026 23:37 (67), 05/27/2026 01:38 (1)
Complete: 🔍
Cache ID: 216::103

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