Quick answers
- Is CVE-2021-23543 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2021-23543 being exploited in the wild.
- How severe is CVE-2021-23543?
- Low severity, with a CVSS score of 3.1, published 13 January 2022.
- Which products and versions are affected?
- realms-shim (npm) SEMVER:introduced=0,last_affected=1.2.2.
- Is there a fix for CVE-2021-23543?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2021-23543 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2021-23543?
- Check whether you run realms-shim (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The vulnerability is a prototype pollution attack (CWE-1321) affecting all versions of realms-shim up to and including version 1.2.2. Prototype pollution allows an attacker to modify the prototype chain of JavaScript objects, which in the context of a sandboxed environment can break the sandbox isolation. The attack is network-reachable and requires no authentication or user interaction; it can be triggered by providing malicious input to the realms-shim library. A successful exploit enables an attacker to bypass the sandbox restrictions and gain full control over the JavaScript execution context, potentially accessing sensitive data or executing arbitrary code with the privileges of the host application.
Affected products
- Agoric realms-shim 0 through 1.2.2
Identifiers
- CVE-2021-23543
- GHSA-q4j7-v27r-fgcx
Timeline
- 2022-01-10: disclosed: Published on NVD
- 2022-01-13: advisory: GHSA advisory published