multiparty service up to 4.2.3/4.2.x Multipart Upload push uncaught exception

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.3$0-$5k0.00

Summaryinfo

A vulnerability was found in multiparty service up to 4.2.3/4.2.x and classified as problematic. The impacted element is the function push of the component Multipart Upload Handler. Such manipulation leads to uncaught exception. This vulnerability is documented as CVE-2026-8161. The attack can be executed remotely. There is not any exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in multiparty service up to 4.2.3/4.2.x. It has been rated as problematic. Affected by this issue is the function push of the component Multipart Upload Handler. The manipulation with an unknown input leads to a uncaught exception vulnerability. Using CWE to declare the problem leads to CWE-248. An exception is thrown from a function, but it is not caught. Impacted is availability. CVE summarizes:

[email protected] and lower versions are vulnerable to denial of service via uncaught exception. By sending a multipart/form-data request with a field name that collides with an inherited Object.prototype property such as __proto__, constructor, or toString, the parser invokes .push() on the inherited prototype value rather than an array, throwing a TypeError that propagates as an uncaught exception and crashes the process. Impact: any service accepting multipart uploads via multiparty is affected. Workarounds: none. Upgrade to [email protected] or higher.

The weakness was released by kq5y and Byambadalai Sumiya. The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-8161 since 05/08/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are known technical details, but no exploit is available.

Upgrading to version 4.3.0 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

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

CNA Base Score: 7.5
CNA Vector (openjs): 🔒

CVSSv2info

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

Exploitinginfo

Class: Uncaught exception
CWE: CWE-248
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: service 4.3.0

Timelineinfo

05/08/2026 CVE reserved
05/12/2026 +4 days Advisory disclosed
05/12/2026 +0 days VulDB entry created
05/12/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Researcher: kq5y, Byambadalai Sumiya
Status: Confirmed

CVE: CVE-2026-8161 (🔒)
GCVE (CVE): GCVE-0-2026-8161
GCVE (VulDB): GCVE-100-362996

Entryinfo

Created: 05/12/2026 11:46
Changes: 05/12/2026 11:46 (65)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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