SB20260423104 - Red Hat Enterprise Linux 9 update for the nodejs:20 module
Published: April 23, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 4 vulnerabilities.
1) Inefficient regular expression complexity (CVE-ID: CVE-2026-26996)
CWE-ID: CWE-1333 - Inefficient Regular Expression Complexity
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to insufficient input validation when processing untrusted input with a regular expressions within "minimatch" function. A remote attacker can pass specially crafted data to the application and perform regular expression denial of service (ReDos) attack.
2) Inefficient regular expression complexity (CVE-ID: CVE-2026-27904)
CWE-ID: CWE-1333 - Inefficient Regular Expression Complexity
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to insufficient input validation when processing untrusted input with a regular expressions. A remote attacker can pass specially crafted data to the application and perform regular expression denial of service (ReDos) attack.
3) Input validation error (CVE-ID: CVE-2026-27135)
CWE-ID: CWE-20 - Improper input validation
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to missing state validation in the nghttp2 session handling logic when processing malformed frames after session termination has been initiated. A remote attacker can send specially crafted frames to cause a denial of service.
For PRIORITY_UPDATE and ALTSVC frames, the affected extension types must be explicitly enabled. Builds with assertions disabled may not crash under the same conditions.
4) Improper error handling (CVE-ID: CVE-2026-21710)
CWE-ID: CWE-388 - Error Handling
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to improper handling of special property names in HTTP headers in req.headersDistinct when parsing incoming HTTP requests. A remote attacker can send a request with a header named __proto__ to trigger a TypeError when the application accesses req.headersDistinct, crashing the Node.js process.
The exception occurs synchronously in a property getter and cannot be caught without wrapping every access in try/catch.
Remediation
Install update from vendor's website.