SB2026073197 - Red Hat Enterprise Linux 10 update for yggdrasil



SB2026073197 - Red Hat Enterprise Linux 10 update for yggdrasil

Published: July 31, 2026

Security Bulletin ID SB2026073197
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 3
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 67% Low 33%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 3 vulnerabilities.


1) Input validation error (CVE-ID: CVE-2026-32281)

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 improper input validation in Certificate.Verify in crypto/x509 when validating certificate chains containing a very large number of policy mappings. A remote attacker can present a specially crafted certificate chain to cause a denial of service.

This only affects validation of otherwise trusted certificate chains issued by a root CA in the VerifyOptions.Roots CertPool or in the system certificate pool.


2) Time-of-check Time-of-use (TOCTOU) Race Condition (CVE-ID: CVE-2026-32282)

CWE-ID: CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a local user to modify file permissions outside the intended root directory.

The vulnerability exists due to improper access control in Root.Chmod and internal/syscall/unix Fchmodat when handling a chmod operation on Linux. A local user can replace the target with a symlink during the check-and-operation window to modify file permissions outside the intended root directory.

Exploitation requires a race condition in which the target is swapped with a symlink while the chmod operation is in progress.


3) Resource exhaustion (CVE-ID: CVE-2026-32280)

CWE-ID: CWE-400 - Resource exhaustion

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 uncontrolled resource consumption in the Certificate.Verify chain-building logic in crypto/x509 when processing a large number of intermediate certificates supplied through VerifyOptions.Intermediates. A remote attacker can provide a large number of intermediate certificates to cause a denial of service.

This affects both direct users of crypto/x509 and users of crypto/tls.


Remediation

Install update from vendor's website.