mcollina msgpack5 up to 6.0.x Streaming Decoder buffer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.5$0-$5k1.39+

Summaryinfo

A vulnerability classified as problematic has been found in mcollina msgpack5 up to 6.0.x. Affected is an unknown function of the component Streaming Decoder. Performing a manipulation results in buffer overflow. This vulnerability is identified as CVE-2026-107299. The attack can be initiated remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in mcollina msgpack5 up to 6.0.x. It has been classified as problematic. This affects some unknown processing of the component Streaming Decoder. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on availability. The summary by CVE is:

msgpack5 is a msgpack v5 implementation for node.js and the browser. Prior to 6.1.0, the streaming decoder treats the reserved MessagePack byte 0xc1 as incomplete input instead of invalid input. When 0xc1 begins a stream, subsequent data remains buffered while the decoder waits for bytes that cannot make the value valid, allowing a remote peer to exhaust memory. This issue is fixed in version 6.1.0.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-107299 since 10/07/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 6.1.0 eliminates this vulnerability.

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: 🔍

CVSSv3info

VulDB Meta Base Score: 5.6
VulDB Meta Temp Score: 5.5

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

CNA Base Score: 5.9
CNA Vector (GitHub_M): 🔒

CVSSv2info

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

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
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: msgpack5 6.1.0

Timelineinfo

10/07/2026 CVE reserved
10/08/2026 +1 days Advisory disclosed
10/08/2026 +0 days VulDB entry created
10/08/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-107299 (🔒)
GCVE (CVE): GCVE-0-2026-107299
GCVE (VulDB): GCVE-100-415491

Entryinfo

Created: 10/08/2026 19:31
Changes: 10/08/2026 19:31 (64)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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