CVE-2026-8657

Exploitation

Public exploit code exists. CISA's assessment records a public proof of concept. That is not a report of exploitation in the wild.

SSVC decision

• ExploitationpocPublic proof-of-concept exploit code exists. Not a report of exploitation in the wild.
• AutomatableyesAn attacker can reliably automate reconnaissance through exploitation, so this scales.
• Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

0.38% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 30.8% of scored records. A rank, not a probability.

NVD base score

7.8 (CVSS v4.0), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

NVD analysis status

Deferred. NVD last modified this record on 2026-07-05.

Red Hat severity

No Red Hat rating. Red Hat rates the CVEs that affect its products.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2026-05-16 05:00Z3 MO AGO

Last updated

2026-08-23 15:25Z11 DAYS AGO

Reserved

2026-05-15

Assigning CNA

snyk

Record state

PUBLISHED

Severity

High (CVSS 8.8)

CNA CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N/E:P

Weaknesses

• CWE-1321Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')Variant

Data version

5.2

Document digest

dc2830ac2e752479fdf2cb639adf643c09d49a707cea43fc6204dd570e286a1b

• security.snyk.iohttps://security.snyk.io/vuln/SNYK-JS-JSONDIFFPATCH-16322990
• security.snyk.iohttps://security.snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-16732792
• gist.github.comhttps://gist.github.com/yuki-matsuhashi/e570fb1579ae1f3190059b622b0473fb
• github.comhttps://github.com/benjamine/jsondiffpatch/blob/96112c35a98f9201dd75d67fcee68a952c79e2fe/packages/jsondiffpatch/src/filters/nested.ts%23L82-L87
• github.comhttps://github.com/benjamine/jsondiffpatch/blob/96112c35a98f9201dd75d67fcee68a952c79e2fe/packages/jsondiffpatch/src/filters/nested.ts%23L107-L115
• github.comhttps://github.com/benjamine/jsondiffpatch/blob/96112c35a98f9201dd75d67fcee68a952c79e2fe/packages/jsondiffpatch/src/formatters/jsonpatch-apply.ts%23L146-L168
• github.comhttps://github.com/benjamine/jsondiffpatch/blob/96112c35a98f9201dd75d67fcee68a952c79e2fe/packages/jsondiffpatch/src/formatters/jsonpatch-apply.ts%23L171-L199
• github.comhttps://github.com/benjamine/jsondiffpatch/commit/381c0125efab49f6f0dbc08317d01d55717672af