- cvss
- 9.8
- version 3.1, GitHub
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- —
- no score, EPSS covers CVEs only
- public exploits
- 0
- none known
Summary
Versions of `realms-shim` prior to 1.2.1 are vulnerable to a Sandbox Breakout. The Realms evaluation function has an option to apply Babel-like transformations to the source code before it reaches the evaluator. One portion of this transform pipeline exposed a primal-Realm object to the rewriting function. Confined code which used the evaluator itself could provide a malicious rewriter function that captured this object, and use it to breach the sandbox.
## Recommendation
Upgrade to version 1.2.1 or later.
Patch / fix
- npm realms-shim 1.2.1
Is GHSA-7cg8-pq9v-x98q in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| GitHub | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | realms-shim | <1.2.1 |
1.2.1 |
References
Sources
- GitHub Advisory GHSA-7cg8-pq9v-x98q
Fencer Intel 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.