CVE-2026-106069
A flaw in Node.js TLS hostname verification can cause a server certificate to be validated against…
- Risk score
- 67/100
- CVSS
- 7.4 v3.0
- Exploit chance (30 days)
- 0.2%
- Published
- 21 Oct 2026
Open in the live forecast Today's forecast
What to know
- What it is
- A flaw in Node.js TLS hostname verification can cause a server certificate to be validated against a different IP address than the one the client connected to, allowing a server at the connected address to be authenticated with a certificate issued for another IP address.
- Affected
- {'products': ['Node.js'], 'packages': [], 'versions': ['26.x', '24.x', '22.x']}
- Fix
- Upgrade to a fixed version of Node.js
- Exploitation
- No known exploitation
Story map
At a glance
Node.js: Red, act today. A buffer overflow vulnerability in the Brotli decoder of Google Brotli versions 1.0.3 through 1.2.0 allows a remote unauthenticated attacker to potentially execute arbitrary code or cause a denial of service.
The flaws
- CVE-2026-106069: A flaw in Node.js TLS hostname verification can cause a server certificate to be validated against… (CVSS 7.4 · EPSS 0%)
- CVE-2026-111497: Out-of-bounds write can lead to remote code execution (CVSS 9.2 · EPSS 1%)
- CVE-2026-48930: Access control flaw (CVSS 9.8 · EPSS 0%)
- CVE-2026-48618: Authentication bypass (CVSS 6.5 · EPSS 3%)
The fix
Fix: Update to the latest available version: 1.0.10 or 1.1.1 or 1.2.1
Who is exposed: {'product': 'Google Brotli', 'packages': ['1.0.3', '1.0.4', '1.0.5', '1.0.6', '1.0.7', '1.0.8', '1.0.9', '1.0.10', '1.1.0', '1.1.1', '1.2.0', '1.2.1'], 'versions': ['1.0.3', '1.0.4', '1.0.5', '1.0.6', '1.0.7', '1.0.8', '1.0.9', '1.0.10', '1.1.0', '1.1.1', '1.2.0', '1.2.1']}
Where it stands
- Exploitation reported in the press
- 1 outlet covering it
How it unfolded
- 21 Oct, Node.js security releases (official): Wednesday, October 21, 2026 Security Releases
- 23 Oct, The Hacker News (press): Researchers Demonstrate Node2Shell RCE Exploit on Node.js Build Using Crafted Brotli Data
- 24 Oct, The Hacker News (press): Brotli Decoder Flaw Behind Node.js RCE Also Affects Bun, Python and Other Widely Used Software
- 25 Oct, Microsoft Security Response Center (official): CVE-2026-111497 Google: CVE-2026-111497 Buffer overflow vulnerability in the Brotli decoder
Connects to
- Same weakness: CWE-295 (CWE-295). 84 other warnings in 30 days
- Same product: Earlier Node.js warnings. 11 in the last 90 days
Why it is Amber
- CVSS 7.4 high
- Remotely exploitable without logging in
- On your watchlist: node.js
- Named in a government or vendor bulletin
Government and vendor bulletins
References
Original description
A flaw in Node.js TLS hostname verification can cause a server certificate to be validated against a different IP address than the one the client connected to, when the host is a non-canonical IPv4 literal with a leading zero, such as `0127.0.0.1`. `tls.checkServerIdentity()` normalizes the host following the WHATWG URL rules, which read a leading-zero octet as octal (`0127.0.0.1` becomes `87.0.0.1`), while the connection is made through the operating system resolver, which on some platforms such as macOS reads it as decimal (`127.0.0.1`). A server at the connected address can then be authenticated with a certificate issued for another IP address. This vulnerability affects Node.js **26.x**, **24.x**, and **22.x**.
Last activity 23 Oct 2026. Patch Forecast updates every hour.