CVE-2026-123866

CVE Enrichment

CVSS: 7.5 HIGH
CISA KEV: Not listed

Description

A use-after-free in Node.js HTTP/2 stream teardown can leak response memory, including the contents of other connections' response buffers, to a peer. When a stream is torn down while a write is still backpressured, for example by a peer RST_STREAM or by the server's own per-stream timeout destroying the stream, the stream's response buffer is freed but a reference to it is still used, so freed or unrelated heap memory is written to the socket instead of the intended response. On Node.js 26.x and 24.x the teardown can be driven purely by a remote peer once the window-size change from 26.9.0 and 24.22.0 is present, and on all supported lines the same defect is reachable through an application-initiated teardown such as a per-stream idle timeout. This vulnerability affects Node.js 26.x, 24.x, and 22.x.

Technical Details

CVSS Version: 3.0
CNA / NVD Source: ce714d77-add3-4f53-aff5-83d477b104bb
Published: 12-Nov-2026 02:17
Last Modified: 12-Nov-2026 02:17
CWE: CWE-416

CVSS Vector


            CVSS:3.0                            AV:N /
                            AC:L /
                            PR:N /
                            UI:N /
                            S:U /
                            C:H /
                            I:N /
                            A:N

CNA Products / Version Status

nodejs · node Source: CNA · ce714d77-add3-4f53-aff5-83d477b104bb
Default status: unaffected

0.0.0 ≤ version < 22.23.5 — affected (semver)
23.0.0 ≤ version < 24.22.3 — affected (semver)
25.0.0 ≤ version < 26.13.1 — affected (semver)

References

Last enrichment sync: 12-Nov-2026 19:31
Sources: NVD · FIRST EPSS · CISA KEV
Latest successful provider update; providers refresh independently.

Reported Context (1)

The memory flaw, CVE-2026-123866, affects all three lines. From 24.22.0 and 26.9.0 onward, a client alone can trigger it. On 22.x and older 24.x and 26.x builds, it can still be triggered when the server itself closes a Node.js Fixes HTTP/2 and HTTPS Flaws That Can Crash Servers or Leak Memory

CVE (2)

People (1)

Products (1)

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