deep-parse-json 1.0.2 - Prototype Pollution

published 2022-11-03 4 y ago modified 2026-06-17 4 mo ago also GHSA-ff9j-pwxg-q5p2 , EUVD-2022-7326

cvss: 5.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.7%; EPSS 0.7% chance of exploitation in 30 days, percentile 54%
public exploits: 0; none known

deep-parse-json version 1.0.2 allows an external attacker to edit or add new properties to an object. This is possible because the application does not correctly validate the incoming JSON keys, thus allowing the '__proto__' property to be edited.

CISA SSVC

Exploitation: Proof of concept is public
Automatable: yes
Technical impact: partial
Assessed: 18 mo ago (2025-05-05)

Exploit prediction

0.73% chance of exploitation in the next 30 days, higher than 54% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

fluidattacks.com https://fluidattacks.com/advisories/buuren/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
NVD	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
CNA	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
GitHub	3.1	5.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Affected packages

ecosystem	package	affected	fixed in
npm	deep-parse-json	<=1.0.2	no fix listed

Affected products

n/a deep-parse-json

Classification

Weakness

CWE-1321 Improperly Controlled Modification of Object Prototype Attributes

References

fluidattacks.com /advisories/buuren/
exploit, third-party-advisory
github.com /sibu-github/deep-parse-json
package, product
nvd.nist.gov /vuln/detail/CVE-2022-42743
advisory
github.com /sibu-github/deep-parse-json/issues/6
web
fluidattacks.com /advisories/buuren
web

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary