Bug 2571836 (CVE-2026-123864) - CVE-2026-123864 nodejs: nodejs: Information disclosure via HTTPS parser re-entrancy
Summary: CVE-2026-123864 nodejs: nodejs: Information disclosure via HTTPS parser re-en...
Keywords:
Status: NEW
Alias: CVE-2026-123864
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
high
high
Target Milestone: ---
Assignee: Product Security DevOps Team
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Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-11-11 18:31 UTC by OSIDB Bzimport
Modified: 2026-11-11 18:41 UTC (History)
0 users

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Description OSIDB Bzimport 2026-11-11 18:31:38 UTC
A re-entrancy flaw in Node.js HTTPS lets an unauthenticated client read memory belonging to other connections, including TLS private keys and other users' requests. TLSWrap::DoWrite() calls ClearOut() directly when asked to write zero bytes; if that write is issued from JavaScript running inside the HTTP parser's on_body callback, ClearOut() decrypts the next TLS record while the parser is still mid-body, re-entering llhttp_execute() and causing a use-after-free and an out-of-bounds heap read. The server then copies that freed or unrelated heap memory into the response for the request body. Triggering it requires a handler that calls res.flushHeaders() before the request body ends and later calls res.end() with a non-empty chunk, and reading the leaked memory requires any ordinary route that echoes or stores a request body. Cleartext node:http is not affected. This vulnerability affects Node.js 26.x, 24.x, and 22.x.


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