CVSS 3.0
8.2 highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:HCVE-2026-123863 Node.js is vulnerable to a remote HTTP/2 denial of service via a reachable assertion in Http2Session teardown
High (8.2) in nodejs node. EPSS 0.5% estimated probability of exploitation activity in the next 30 days.
On this page
A reachable assertion in Node.js HTTP/2 session teardown lets any unauthenticated client abort the server, over both TLS and cleartext. A client can arrange for an Http2Stream that still holds nghttp2-allocated header buffers to outlive its session: the stream is removed from the session's stream set but never detached, so when ~Http2Session() runs the memory accounting is nonzero and the CHECK_EQ(current_nghttp2_memory_, 0) assertion fails, terminating the process. The trigger needs only a default http2 server whose handler responds before the request body has ended, which is typical. It is a variant of CVE-2024-27983 that the earlier fix did not cover, because that fix only detached streams still tracked in the session. This vulnerability affects Node.js 26.x (since 26.9.0) and 24.x (since 24.22.0).
Severity
- EPSS
- 0.5% estimated probability of exploitation activity in the next 30 days; 41st percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CWE
- CWE-617 Reachable Assertion
- Published
- Modified
- Assigned by
- openjs (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| nodejs node | from 24.0.0 before 24.22.3 |
| nodejs node | from 25.0.0 before 26.13.1 |
Fix and patched versions
- Red Hat, Alpine, Alpaquita, BellSoft Hardened Containers: fixed package versions per release
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Debian | 12, 13, 14 | nodejs | no fix listed | DEBIAN-CVE-2026-123863 |
| Ubuntu | 24.04:LTS, 26.04:LTS, 26.10 and 5 more | nodejs | no fix listed | UBUNTU-CVE-2026-123863 |
| Red Hat | hummingbird:1 | nodejs22, nodejs22-bin, nodejs22-docs and 4 more | 1:22.23.4-2.3.2.3.1.hum1 | RHSA-2026:93603 |
| Red Hat | hummingbird:1 | nodejs22-npm | 1:10.9.9-1.22.23.4.2.3.2.3.1.hum1 | RHSA-2026:93603 |
| Red Hat | hummingbird:1 | nodejs24, nodejs24-bin, nodejs24-docs and 3 more | 1:24.22.3-0.1.hum1 | RHSA-2026:99435 |
| Red Hat | hummingbird:1 | nodejs24-npm | 2:11.19.1-1.24.22.3.0.1.hum1 | RHSA-2026:99435 |
| Red Hat | hummingbird:1 | nodejs24-npm-bin | 2:24.22.3-0.1.hum1 | RHSA-2026:99435 |
| Red Hat | hummingbird:1 | nodejs26, nodejs26-bin, nodejs26-docs and 4 more | 1:26.13.1-0.1.hum1 | RHSA-2026:99436 |
| Red Hat | hummingbird:1 | nodejs26-npm | 1:11.20.0-1.26.13.1.0.1.hum1 | RHSA-2026:99436 |
| Red Hat | hummingbird:1 | v8-12.4-devel | 3:12.4.254.21-1.22.23.4.2.3.2.3.1.hum1 | RHSA-2026:93603 |
| Alpine | v3.21, v3.22 | nodejs | 22.23.5-r0 | ALPINE-CVE-2026-123863 |
| Alpine | v3.23, v3.24 | nodejs | 24.22.3-r0 | ALPINE-CVE-2026-123863 |
| Alpine | v3.24 | nodejs-current | 26.13.1-r0 | ALPINE-CVE-2026-123863 |
| Alpaquita | stream | nodejs22 | 22.23.5-r0 | BELL-CVE-2026-123863 |
| Alpaquita | stream | nodejs24 | 24.22.3-r0 | BELL-CVE-2026-123863 |
| Alpaquita | stream | nodejs26 | 26.13.1-r0 | BELL-CVE-2026-123863 |
| BellSoft Hardened Containers | stream | nodejs22 | 22.23.5-r0 | BELL-CVE-2026-123863 |
| BellSoft Hardened Containers | stream | nodejs24 | 24.22.3-r0 | BELL-CVE-2026-123863 |
| BellSoft Hardened Containers | stream | nodejs26 | 26.13.1-r0 | BELL-CVE-2026-123863 |
From the distributions' data via OSV.dev: the Debian Security Tracker; Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0; Red Hat Security Data © Red Hat, Inc., CC BY 4.0; the Alpine secdb, CC BY-SA 4.0; BellSoft's OSV database, MIT. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Debian · Ubuntu · Red Hat · Alpine · Alpaquita · BellSoft Hardened Containers.
Red Hat
Red Hat rates this Important.
This vulnerability is rated as Important severity because an unauthenticated remote attacker can trigger an unexpected server crash, causing a full denial of service without requiring authentication or user interaction. In Red Hat environments, the impact directly affects deployments hosting Node.js applications that utilize the built-in HTTP/2 server module exposed to untrusted network traffic. Applications serving requests exclusively over HTTP/1.1 or situated behind reverse proxies that terminate HTTP/2 traffic are not exposed to this failure path.
Terminate HTTP/2 at a trusted reverse proxy and proxy HTTP/1.1 to Node.js (see CME-202). Restrict direct Node.js HTTP/2 listeners to trusted networks only.
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Hardened Images | nodejs22-main-10.9.9-1.22.23.4.2.3.2.3.1.hum1 | Fixed 2026-11-02 | RHSA-2026:93603 |
| Red Hat Hardened Images | nodejs22-main-22.23.4-2.3.2.3.1.hum1 | Fixed 2026-11-02 | RHSA-2026:93603 |
| Red Hat Enterprise Linux 10 | nodejs22 | Not affected | |
| Red Hat Enterprise Linux 10 | nodejs24 | Affected | |
| Red Hat Enterprise Linux 10 | nodejs26 | Affected | |
| Red Hat Enterprise Linux 8 | nodejs:22/nodejs | Not affected | |
| Red Hat Enterprise Linux 8 | nodejs:24/nodejs | Affected | |
| Red Hat Enterprise Linux 9 | nodejs:22/nodejs | Not affected | |
| Red Hat Enterprise Linux 9 | nodejs:24/nodejs | Affected | |
| Red Hat Enterprise Linux 9 | nodejs:26/nodejs | Affected | |
| Red Hat Hardened Images | hi/nodejs | Not affected | |
| Red Hat Hardened Images | nodejs20 | Will not fix | |
| Red Hat Hardened Images | nodejs24 | Affected | |
| Red Hat Hardened Images | nodejs25 | Will not fix | |
| Red Hat Hardened Images | nodejs26 | Affected | |
| Red Hat Hardened Images | npm12 | Not affected |
Contains Red Hat Security Data © Red Hat, Inc., licensed under CC BY 4.0. Source: https://access.redhat.com/security/data. Modified: reformatted. Red Hat's page for CVE-2026-123863.