CVE-2025-27209 Denial of service in node
Attackers can cause denial of service in Node.js v24 by exploiting hash collisions in the V8 engine's string hashing implementation.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-27209?
CVE-2025-27209 is a high-severity denial of service vulnerability in nodejs node, published on 18 Jul 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The V8 release used in Node.js v24.0.0 has changed how string hashes are computed using rapidhash. This implementation re-introduces the HashDoS vulnerability as an attacker who can control the strings to be hashed can generate many hash collisions - an attacker can generate collisions even without knowing the hash-seed. * This vulnerability affects Node.js v24.x users.
Weakness: CWE-407
Which versions are affected by CVE-2025-27209?
2 open source packages ship an affected version, including node and node-min.
| Package | Affected | Fixed in |
|---|---|---|
node Bitnami | From 24.0.0 | 24.4.1 |
node-min Bitnami | From 24.0.0 | 24.4.1 |
How do I fix CVE-2025-27209?
Upgrade node to 24.4.1 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2025-27209 being exploited?
There is no known exploitation of CVE-2025-27209 in the wild and no public exploit code.
Sources
Also known as BIT-node-2025-27209, BIT-node-min-2025-27209, GHSA-qr33-gf7m-pq45, MINI-jw94-h8cm-5xr2.