GHSA-9c47-m6qq-7p4h · Severity: high · Ecosystem: npm — Prototype Pollution in JSON5 via Parse Method
JSON5 is an extension to the popular JSON file format that aims to be easier to write and maintain by hand (e.g. for config files). The `parse` method of the JSON5 library before and including versions 1.0.1 and 2.2.1 does not restrict parsing of keys named `__proto__`, allowing specially crafted strings to pollute the prototype of the resulting object. This vulnerability pollutes the prototype of the object returned by `JSON5.parse` and not the global Object prototype, which is the commonly understood definition of Prototype Pollution. However, polluting the prototype of a single object can have significant security impact for an application if the object is later used in trusted operations. This vulnerability could allow an attacker to set arbitrary and unexpected keys on the object returned from `JSON5.parse`. The actual impact will depend on how applications utilize the returned object and how they filter unwanted keys, but could include denial of service, cross-site scripting, elevation of privilege, and in extreme cases, remote code execution. `JSON5.parse` should restrict parsing of `__proto__` keys when parsing JSON strings to objects. As a point of reference, the `JSON.parse` method included in JavaScript ignores `__proto__` keys. Simply changing `JSON5.parse` to `JSON.parse` in the examples above mitigates this vulnerability. This vulnerability is patched in json5 versions 1.0.2, 2.2.2, and later.
Conclusion & alert: CVE-2022-46175 is rated High Exploit Risk (75.8/100): CVSS High severity, with high exploitation likelihood (EPSS 42.30%, 98th percentile). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
| EDB-ID | Source | Kind | Published | Link |
|---|---|---|---|---|
| — | nvd_ref | exploit_tag | Exploit-DB ↗ |
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-04 | 44.08% | 42.30% | -1.77% |
| 2 | 2026-05-22 | 46.50% | 44.08% | -2.42% |
| 3 | 2026-03-04 | — | 46.50% | — |
Full EPSS history (76 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.1 | 3.1 | HIGH |
|
1.6 | 5.5 | [email protected] |
| 8.8 | 3.1 | HIGH |
|
2.8 | 5.9 | [email protected] |
GHSA-9c47-m6qq-7p4h · Severity: high · Ecosystem: npm — Prototype Pollution in JSON5 via Parse Method
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2022-46175 not yet assigned priority: Debian including 1 source packages (node-json5), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2022-46175 |
redhat
|
medium | — | https://access.redhat.com/security/cve/CVE-2022-46175 |
ubuntu
|
medium | CVE-2022-46175 medium priority: Ubuntu including 1 source packages (node-json5), 13 status rows across 13 suites (bionic, focal, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 5, ignored 4, released 4. | https://ubuntu.com/security/CVE-2022-46175 |
| URL | Tags |
|---|---|
| https://github.com/json5/json5/issues/199 | Issue Tracking Patch Third Party Advisory |
| https://github.com/json5/json5/issues/295 | Issue Tracking Third Party Advisory |
| https://github.com/json5/json5/pull/298 | Patch Third Party Advisory |
| https://github.com/json5/json5/security/advisories/GHSA-9c47-m6qq-7p4h | Exploit Third Party Advisory |
| https://lists.debian.org/debian-lts-announce/2023/11/msg00021.html | |
| https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/3S26TLPLVFAJTUN3VIXFDEBEXDYO22CE/ |