CVE-2026-56848: A flaw in Node.js HTTP/2 handling allows `nghttp2_session_mem_send()` to be called re-entrantly while `nghttp2_session_m…
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**.
- Published by source
- 2026-08-04
- First seen by Reality Radar
- 2026-10-24
- Last verified
- 2026-10-24
What the official notice says
Risk: CVSS 7.5
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Sources
- NIST National Vulnerability Database Tier A · official published 2026-08-04
Evidence ledger
Every piece of evidence we store is appended to a public hash chain, so later edits are detectable. Anyone can re-verify it.
| Entry | Kind | Observed | Evidence hash | Entry hash |
|---|---|---|---|---|
| #1519 | new | 2026-10-24 | 9f15c5a28443…392f1f | 7e0e577b634d…81e613 |
Chain head: #1565 7d9afd922511…68b9c7