CVE-2025-40780 | Cache poisoning due to weak PRNG

In specific circumstances, due to a weakness in the Pseudo Random Number Generator (PRNG) that is used, it is possible for an attacker to predict the source port and query ID that BIND will use. This issue affects BIND 9 versions 9.16.0 through 9.16.50, 9.18.0 through 9.18.39, 9.20.0 through 9.20.13, 9.21.0 through 9.21.12, 9.16.8-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.39-S1, and 9.20.9-S1 through 9.20.13-S1.

Published: 2025-10-22 Last update: 2026-04-15 Assigner: [email protected] Source: [email protected]
NVD Status：Deferred，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-40780 is rated Moderate Risk (44.7/100): CVSS High severity, with low exploitation likelihood (EPSS 0.37%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-40780

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.01% 0.37% +0.36%
2 2025-10-23 — 0.01% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-40780

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.6 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 4.0 [email protected]

Weakness enumeration for CVE-2025-40780

OS Trackers for CVE-2025-40780

vendor priority summary link
alpine high CVE-2025-40780: 1 source package rows (bind); 5 state rows across 5 repos (3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 5, open 0. https://security.alpinelinux.org/vuln/CVE-2025-40780
debian not yet assigned CVE-2025-40780 not yet assigned priority: Debian including 1 source packages (bind9), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2025-40780
redhat high — https://access.redhat.com/security/cve/CVE-2025-40780
suse high — https://www.suse.com/security/cve/CVE-2025-40780/
ubuntu medium CVE-2025-40780 medium priority: Ubuntu including 3 source packages (bind9, bind9-libs, isc-dhcp), 24 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): needs-triage 9, released 6, not-affected 4, DNE 3, ignored 1, needed 1. https://ubuntu.com/security/CVE-2025-40780

Affected software / configurations for CVE-2025-40780

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2025-40780

cvelogic Threat Intelligence