CVE-2026-56848
Received
Received - Intake
Heap Use After Free in Node.js HTTP/2 Handling
Vulnerability report for CVE-2026-56848, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-08-04
Last updated on: 2026-08-04
Assigner: HackerOne
Description
Description
A flaw in Node.js HTTP/2 handling allows `nghttp2_session_mem_send()` to be called re-entrantly while `nghttp2_session_mem_recv()` is executing, resulting in a heap-use-after-free.
This vulnerability affects Node.js **26.x**, **24.x**, and **22.x**.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| nodejs | node.js | From 26.x (inc) |
| nodejs | node.js | From 24.x (inc) |
| nodejs | node.js | From 22.x (inc) |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-416 | 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 Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer. |
