Unauthenticated server crash via HTTP/2 teardown race
Published Apr 9, 2024 · Updated Nov 4, 2025
Race condition in affected Node.js HTTP/2 servers allows remote attackers to crash the process via crafted CONTINUATION frames. The Http2Session destructor frees a session while nghttp2 is still processing and retaining header data because active streams are not closed first. An unauthenticated client must reach an HTTP/2 endpoint and abruptly close TCP during header processing; successful exploitation terminates the server process and interrupts service.
Summary
What happened
Race condition in affected Node.js HTTP/2 servers allows remote attackers to crash the process via crafted CONTINUATION frames. The Http2Session destructor frees a session while nghttp2 is still processing and retaining header data because active streams are not closed first. An unauthenticated client must reach an HTTP/2 endpoint and abruptly close TCP during header processing; successful exploitation terminates the server process and interrupts service.
The record
- CVE
- CVE-2024-27983
- Published
- Apr 9, 2024
- Updated
- Nov 4, 2025
- Vendor
- Node.js
- Product
- Node.js
- Classifications
- CWE-362, CAPEC-26, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 9, 2024CVE publishedPublication date reported by the CVE source.
- Nov 4, 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.*
- Affected versionversion=13.0 <13.*
- Affected versionversion=14.0 <14.*
- Affected versionversion=15.0 <15.*
- Affected versionversion=16.0 <16.*
- Affected versionversion=17.0 <17.*
- Affected versionversion=18.0 <18.20.1
- Affected versionversion=19.0 <19.*
- Affected versionversion=20.0 <20.12.1
- Affected versionversion=21.0 <21.7.2
- 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?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
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
- CVE-2024-27983 Node.js HTTP/2 continuation-flood proof of conceptfunctional · demonstrated
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