CVE-2026-6594 brikcss merge prototype pollution
Remote attackers can exploit prototype pollution in brikcss merge to execute arbitrary code or escalate privileges via manipulated object properties.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-6594?
CVE-2026-6594 is a medium-severity code injection vulnerability in brikcss merge, published on 20 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A vulnerability was determined in brikcss merge up to 1.3.0. This affects an unknown part. Executing a manipulation of the argument __proto__/constructor.prototype/prototype can lead to improperly controlled modification of object prototype attributes. The attack may be performed from remote. The vendor was contacted early about this disclosure but did not respond in any way.
Which versions are affected by CVE-2026-6594?
2 open source packages ship an affected version, including @brikcss/merge.
| Package | Affected | Fixed in |
|---|---|---|
@brikcss/merge npm | All versions to 1.3.1 | None |
@brikcss/merge npm | All versions to 1.3.1 | None |
How do I fix CVE-2026-6594?
No fix has been published for CVE-2026-6594 yet. Limit exposure of the affected software until one is available.
Upgrade, and never evaluate templates, expressions or code built from user input. More about Code injection.
Is CVE-2026-6594 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-6594 exists.
Sources
Also known as GHSA-3jc6-6r48-v6qf.