What is RHSA-2025:21740?

RHSA-2025:21740 is a security advisory published by Red Hat Product Security with High severity. Red Hat Security Advisory: bind security update

Which CVE IDs does RHSA-2025:21740 cover?

RHSA-2025:21740 covers the following CVE IDs: CVE-2021-25220, CVE-2025-40778. Each CVE has its own detail page on EchelonGraph Pulse with the synthesized EG score.

What is the CVSS v3 score of RHSA-2025:21740?

RHSA-2025:21740 has a CVSS v3 base score of 8.6, published by Red Hat Product Security.

RHSA-2025:21740HighCVSS 8.6

Red Hat Security Advisory: bind security update

Vendor

Red Hat Product Security

Published

November 19, 2025

Last Modified

July 7, 2026

🔗 CVE IDs covered (2)

CVE-2021-25220 →CVE-2025-40778 →

📋 Description

CVE-2021-25220 — bind: DNS forwarders - cache poisoning vulnerability CVE-2025-40778 — bind: Cache poisoning attacks with unsolicited RRs

🔗 References (5)

selfhttps://access.redhat.com/errata/RHSA-2025:21740
externalhttps://access.redhat.com/security/updates/classification/#important
externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2064512
externalhttps://bugzilla.redhat.com/show_bug.cgi?id=2405827
selfhttps://security.access.redhat.com/data/csaf/v2/advisories/2025/rhsa-2025_21740.json