jsondiffpatch up to 0.7.5 jsonpatch.patch jsondiffpatch.patch prototype pollution

CVSS Meta Temp Score
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CTI Interest Score
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7.2$0-$5k0.00

Summaryinfo

A vulnerability was found in jsondiffpatch up to 0.7.5. It has been classified as critical. This issue affects the function jsondiffpatch.patch of the file jsondiffpatch/formatters/jsonpatch.patch. The manipulation leads to prototype pollution. This vulnerability is listed as CVE-2026-8657. The attack may be initiated remotely. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as critical, has been found in jsondiffpatch up to 0.7.5. This issue affects the function jsondiffpatch.patch of the file jsondiffpatch/formatters/jsonpatch.patch. 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 integrity, and availability. The summary by CVE is:

Versions of the package jsondiffpatch before 0.7.6 are vulnerable to Prototype Pollution via the jsondiffpatch.patch() and jsondiffpatch/formatters/jsonpatch.patch() APIs. An attacker can perform prototype pollution by supplying crafted delta or JSON Patch documents, as attacker-controlled property names and path segments are used to traverse and modify objects without restricting access to special properties like __proto__ or constructor.prototype, allowing modification of Object.prototype.

The advisory is shared at security.snyk.io. The identification of this vulnerability is CVE-2026-8657 since 05/15/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1059 for this issue.

Upgrading to version 0.7.6 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-30670). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

Version

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: 7.3
VulDB Meta Temp Score: 7.2

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 8.2
CNA Vector (snyk): 🔒

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: 🔒

Upgrade: jsondiffpatch 0.7.6

Timelineinfo

05/15/2026 CVE reserved
05/16/2026 +1 days Advisory disclosed
05/16/2026 +0 days VulDB entry created
05/21/2026 +5 days VulDB entry last update

Sourcesinfo

Advisory: SNYK-JS-JSONDIFFPATCH-16322990
Status: Confirmed

CVE: CVE-2026-8657 (🔒)
GCVE (CVE): GCVE-0-2026-8657
GCVE (VulDB): GCVE-100-364313
EUVD: 🔒

Entryinfo

Created: 05/16/2026 08:22
Updated: 05/21/2026 11:20
Changes: 05/16/2026 08:22 (76), 05/16/2026 08:59 (1), 05/21/2026 11:20 (1)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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