CVE-2026-16266

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.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• 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

0.42% probability of exploitation activity in the next 30 days.

EPSS percentile

Ranks above 35.1% of scored records. A rank, not a probability.

NVD base score

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

NVD CVSS vector

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

Awaiting Analysis. NVD last modified this record on 2026-07-23.

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

2026-07-21 05:00Z1 MO AGO

Last updated

2026-07-21 14:52Z1 MO AGO

Reserved

2026-07-20

Assigning CNA

snyk

Record state

PUBLISHED

Severity

Medium (CVSS 6.3)

CNA CVSS vector

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

Weaknesses

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

Data version

5.2

Document digest

7c0b1c9e28992d2e82d6fd43da57da23355a0f64a2cc9d0cac15ed6c110ece9b

• security.snyk.iohttps://security.snyk.io/vuln/SNYK-JS-MONGOOBJECT-13816714
• github.comhttps://github.com/longshotlabs/mongo-object/issues/27
• github.comhttps://github.com/longshotlabs/mongo-object/blob/4f7a570f2a2fcfa9417b7870d5f859e9574ec73c/src/util.ts%23L251
• github.comhttps://github.com/longshotlabs/mongo-object/commit/638314107d8b397e5453c28e41729522b3e8d67c