Updated: 2026-02-27 03:42:56.769809
Description:
The Closest Encloser Proof aspect of the DNS protocol (in RFC 5155 when RFC 9276 guidance is skipped) allows remote attackers to cause a denial of service (CPU consumption for SHA-1 computations) via DNSSEC responses in a random subdomain attack, aka the "NSEC3" issue. The RFC 5155 specification implies that an algorithm must perform thousands of iterations of a hash function in certain situations.
| Links | NIST | CIRCL | RHEL | Ubuntu |
| Severity | Score | |
|---|---|---|
| CVSS Version 2.x | 0.0 | |
| CVSS Version 3.x | HIGH | 7.5 |
| OS name | Project name | Version | Score | Severity | Status | Errata | Last updated | Statement |
|---|---|---|---|---|---|---|---|---|
| CloudLinux 6 ELS | bind | 9.8.2 | 7.5 | HIGH | Released | CLSA-2024:1710439896 | 2024-03-25 09:51:18 | |
| CloudLinux 7 ELS | dhcp | 4.2.5 | 7.5 | HIGH | Already Fixed | 2025-12-23 01:56:28 | ||
| CloudLinux 7 ELS | bind | 9.11.4 | 7.5 | HIGH | Already Fixed | 2024-10-02 14:26:04 | ||
| CloudLinux 7 ELS | unbound | 1.6.6 | 7.5 | HIGH | Released | CLSA-2025:1765309238 | 2026-01-22 05:30:17 | |
| Oracle Linux 6 ELS | dhcp | 4.1.1 | 7.5 | HIGH | Not Vulnerable | 2024-10-11 10:45:33 | ||
| Oracle Linux 6 ELS | bind | 9.8.2 | 7.5 | HIGH | Released | CLSA-2024:1710437080 | 2024-03-14 14:09:18 | |
| Oracle Linux 7 ELS | unbound | 1.6.6 | 7.5 | HIGH | Released | CLSA-2025:1765282338 | 2025-12-09 20:55:40 | |
| Oracle Linux 7 ELS | bind | 9.11.4 | 7.5 | HIGH | Already Fixed | 2025-11-07 23:02:48 | ||
| Oracle Linux 7 ELS | dhcp | 4.2.5 | 7.5 | HIGH | Already Fixed | 2025-11-07 23:02:47 | ||
| RHEL 7 ELS | unbound | 1.6.6 | 7.5 | HIGH | Released | CLSA-2025:1756230743 | 2025-08-28 09:20:09 |