Apache log4net up to 3.4.x aspnet-request pattern converter exceptional condition

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.2$0-$5k0.60

Summaryinfo

A vulnerability was found in Apache log4net up to 3.4.x. It has been declared as problematic. Affected is an unknown function of the component aspnet-request pattern converter. Executing a manipulation can lead to exceptional condition. This vulnerability is registered as CVE-2026-105242. It is possible to launch the attack remotely. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Apache log4net up to 3.4.x and classified as problematic. This vulnerability affects some unknown processing of the component aspnet-request pattern converter. The manipulation with an unknown input leads to a exceptional condition vulnerability. The CWE definition for the vulnerability is CWE-755. The product does not handle or incorrectly handles an exceptional condition. As an impact it is known to affect integrity. CVE summarizes:

Improper Handling of Exceptional Conditions vulnerability in the aspnet-request pattern converter of Apache log4net. Reading request parameters triggers ASP.NET request validation, so a request carrying content such as markup made the layout throw and the appender discarded the whole event. A sender could suppress the log record of their own request. Only applications on ASP.NET for .NET Framework whose layout uses %aspnet-request are affected. This issue affects Apache log4net: from 1.2.11 before 3.5.0. Users are recommended to upgrade to version 3.5.0, which fixes the issue.

The advisory is available at github.com. This vulnerability was named CVE-2026-105242 since 10/04/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 10/06/2026).

Upgrading to version 3.5.0 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.2

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.3
CNA Vector (apache): 🔒

CVSSv2info

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

Exploitinginfo

Class: Exceptional condition
CWE: CWE-755
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: log4net 3.5.0

Timelineinfo

10/04/2026 CVE reserved
10/06/2026 +2 days Advisory disclosed
10/06/2026 +0 days VulDB entry created
10/06/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: apache.org

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-105242 (🔒)
GCVE (CVE): GCVE-0-2026-105242
GCVE (VulDB): GCVE-100-414490

Entryinfo

Created: 10/06/2026 22:02
Changes: 10/06/2026 22:02 (64)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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