piscina prototype pollution

CVSS Meta Temp Score
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CTI Interest Score
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6.7$0-$5k0.00

Summaryinfo

A vulnerability categorized as problematic has been discovered in piscina. This impacts an unknown function. Such manipulation leads to prototype pollution. This vulnerability is referenced as CVE-2026-55388. It is possible to launch the attack remotely. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in piscina (affected version unknown). It has been rated as problematic. Affected by this issue is an unknown functionality. The manipulation with an unknown input leads to a prototype pollution vulnerability. Using CWE to declare the problem leads to CWE-1321. The product receives input from an upstream component that specifies attributes that are to be initialized or updated in an object, but it does not properly control modifications of attributes of the object prototype. Impacted is confidentiality, integrity, and availability. CVE summarizes:

piscina is a node.js worker pool implementation. Prior to 6.0.0-rc.2, 5.2.0, and 4.9.3, piscina's constructor and run() paths read the filename option via plain member access. Both reads fall through the prototype chain when the caller's options object doesn't have filename as an own property. When Object.prototype.filename is polluted upstream the inherited value flows to worker_threads.Worker import and the attacker's .mjs runs in the worker. This vulnerability is fixed in 6.0.0-rc.2, 5.2.0, and 4.9.3.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-55388. The exploitation is known to be difficult. The attack may be launched remotely. No form of authentication is required for exploitation. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1059 by the MITRE ATT&CK project.

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Productinfo

Name

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.8
VulDB Meta Temp Score: 6.7

VulDB Base Score: 5.6
VulDB Temp Score: 5.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.1
CNA Vector: 🔒

CVSSv2info

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

Exploitinginfo

Class: Prototype pollution
CWE: CWE-1321 / CWE-94 / 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: Upgrade
Status: 🔍

0-Day Time: 🔒

Timelineinfo

06/21/2026 Advisory disclosed
06/21/2026 +0 days VulDB entry created
06/27/2026 +6 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-55388 (🔒)
GCVE (CVE): GCVE-0-2026-55388
GCVE (VulDB): GCVE-100-372590

Entryinfo

Created: 06/21/2026 05:58
Updated: 06/27/2026 16:54
Changes: 06/21/2026 05:58 (47), 06/27/2026 16:54 (12)
Complete: 🔍
Cache ID: 216::103

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