node: Use After Free
CVE-2026-123874 is a high-severity use after free vulnerability in node from Node.js, with a CVSS 3.0 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 24.22.3, 26.13.1 as the first without the flaw, so updating node to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.47% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update node to 24.22.3 or 26.13.1, whichever matches your release line, or a later version.
- Read the advisory on cna.openjsf.org for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Node.js | node | 24.0.0 up to, but not including, 24.22.3; 25.0.0 up to, but not including, 26.13.1 | 24.22.3, 26.13.1 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- NoneNo data is disclosed.
- Integrity
- NoneNothing can be modified.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by CNA.
Official description
A use-after-free in Node.js HTTP/2 lets an unauthenticated client corrupt server memory, over both TLS and cleartext, when the server serves files with respondWithFile() or respondWithFD(). A client can make the server free an Http2Stream while a write request that points to it is still queued on the socket; when that write completes, the code dereferences and makes a virtual call through the freed object. The only precondition is that the application serves a file with stream.respondWithFile() or stream.respondWithFD(), with default settings otherwise. This vulnerability affects Node.js 26.x (since 26.9.0) and 24.x (since 24.22.0).
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Use After Free
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
Timeline
- CVE record published.
- Record last changed materially (score, affected products, status or references).
References
Advisories
Other references
Other vulnerabilities in node
- 7.5 High severity
- 8.1 High severity
- 7.5 High severity
- 7.5 High severity
- 8.1 High severity
- 8.2 High severity
Recent Use After Free vulnerabilities
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 8.8 High severity
- 9.6 Critical severity
- 7.5 High severity
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