TLS identity bypass via URI SAN acceptance
Published Feb 24, 2022 · Updated Apr 30, 2025
Improper certificate validation in Node.js allows remote attackers to bypass TLS identity checks through crafted URI SANs. The tls.checkServerIdentity path parsed uniformResourceIdentifier SANs as URLs, compared only the URI hostname, and accepted that SAN type regardless of application protocol. Exploitation requires a TLS connection to an attacker-controlled endpoint presenting a URI-SAN certificate from an intermediate whose name constraints do not restrict URIs, enabling server impersonation and protected-data exposure or modification.
Summary
What happened
Improper certificate validation in Node.js allows remote attackers to bypass TLS identity checks through crafted URI SANs. The tls.checkServerIdentity path parsed uniformResourceIdentifier SANs as URLs, compared only the URI hostname, and accepted that SAN type regardless of application protocol. Exploitation requires a TLS connection to an attacker-controlled endpoint presenting a URI-SAN certificate from an intermediate whose name constraints do not restrict URIs, enabling server impersonation and protected-data exposure or modification.
The record
- CVE
- CVE-2021-44531
- Published
- Feb 24, 2022
- Updated
- Apr 30, 2025
- Vendor
- Node.js
- Product
- Node.js
- Classifications
- CWE-295
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Feb 24, 2022CVE publishedPublication date reported by the CVE source.
- Apr 30, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=10.0 <10.*
- Affected versionversion=11.0 <11.*
- Affected versionversion=12.0 <12.22.9
- Affected versionversion=13.0 <13.*
- Affected versionversion=14.0 <14.18.3
- Affected versionversion=15.0 <15.*
- Affected versionversion=16.0 <16.13.2
- Affected versionversion=17.0 <17.3.1
- Affected versionversion=4.0 <4.*
- Affected versionversion=5.0 <5.*
- Affected versionversion=6.0 <6.*
- Affected versionversion=7.0 <7.*
- Affected versionversion=8.0 <8.*
- Affected versionversion=9.0 <9.*
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo