SB2026042093 - Red Hat Enterprise Linux 9 update for runc
Published: April 20, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 4 secuirty vulnerabilities.
1) Resource exhaustion (CVE-ID: CVE-2025-61729)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to application does not properly control consumption of internal resources within the HostnameError.Error() function in crypto/x509 when printing error string for host certificate validation. A remote attacker can supply a specially crafted certificate to the application and trigger resource exhaustion, leading to a denial of service condition.
2) Resource exhaustion (CVE-ID: CVE-2025-61726)
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to application does not properly control consumption of internal resources within the Request.ParseForm method in net/http when parsing a URL-encoded form. A remote attacker can pass an overly large request with a large number of key-value pairs and consume all available memory on the system.
3) Improper Certificate Validation (CVE-ID: CVE-2025-68121)
The vulnerability allows a remote attacker to compromise the target system.
The vulnerability exists due to improper certificate validation within HTTP/3 connections. A remote attacker can cause cause a client to resume a session with a server that it would not have resumed with during the initial handshake
4) Input validation error (CVE-ID: CVE-2026-25679)
The vulnerability allows a remote attacker to bypass URL parsing validation and potentially access unintended resources.
The vulnerability exists due to insufficient validation in net/url.Parse when handling IPv6 literals not located at the start of the host component. A remote attacker can send a specially crafted URL with an IPv6 literal preceded by garbage characters to bypass proper parsing and potentially redirect requests.
This issue affects any application using net/url.Parse to process untrusted URLs. The incorrect parsing may lead to misrouting or injection of unintended host components.
Remediation
Install update from vendor's website.