VulnerabilityModified
CVE-2021-23543
All versions of package realms-shim are vulnerable to Sandbox Bypass via a Prototype Pollution attack vector.
CRITICAL 9.8EPSS 1.76%
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.76%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
All versions of package realms-shim are vulnerable to Sandbox Bypass via a Prototype Pollution attack vector.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 1.76% probability · 78th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-1321
- Affected
- agoric/realms-shim
- Source
- report@snyk.io
EPSS 1.8% 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
- https://snyk.io/vuln/SNYK-JS-REALMSSHIM-2309908Exploit, Third Party Advisory
- https://www.npmjs.com/package/realms-shimProduct, Third Party Advisory
- https://snyk.io/vuln/SNYK-JS-REALMSSHIM-2309908Exploit, Third Party Advisory
- https://www.npmjs.com/package/realms-shimProduct, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.