VulnerabilityDeferred

CVE-2026-77413

Prior to 1.8.8 and 2.2.0, the src/functions.js lookup function lacked an Object.prototype.hasOwnProperty check and allowed crafted expressions to access inherited prototype members.

CRITICAL 9.3EPSS 0.72%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.72%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

JSONata is a JSON query and transformation language. Prior to 1.8.8 and 2.2.0, the src/functions.js lookup function lacked an Object.prototype.hasOwnProperty check and allowed crafted expressions to access inherited prototype members. An attacker able to supply an expression could use inherited prototype setters and getters, constructor access, valueOf, and process.getBuiltinModule to reach the child_process module and execute arbitrary code with the privileges of the host process. This issue is fixed in versions 1.8.8 and 2.2.0.

CVSS 4.0: 9.3 CRITICALCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS: 0.72% probability · 54th percentile
Public exploits: None in Exploit-DB
CISA KEV: Not listed
Weakness: CWE-94
Source: security-advisories@github.com

EPSS trend

EPSS 0.7% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.