What’s Vulnerable › Vulnerabilities

CVE-2019-25033

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-04-27 · updated 2026-06-17
• Weakness: CWE-190

Description

Unbound before 1.9.5 allows an integer overflow in the regional allocator via the ALIGN_UP macro. NOTE: The vendor disputes that this is a vulnerability. Although the code may be vulnerable, a running Unbound installation cannot be remotely or locally exploited

Affected products

• Debian Linux: 9.0
• NLnet Labs Unbound: before 1.9.5 — fixed in 1.9.5

How to fix

Upgrade to a fixed version: NLnet Labs Unbound 1.9.5. Check the vendor advisory for mitigations.

References

• https://lists.debian.org/debian-lts-announce/2021/05/msg00007.html
• https://ostif.org/our-audit-of-unbound-dns-by-x41-d-sec-full-results/
• https://security.netapp.com/advisory/ntap-20210507-0007/
• https://lists.debian.org/debian-lts-announce/2021/05/msg00007.html
• https://ostif.org/our-audit-of-unbound-dns-by-x41-d-sec-full-results/
• https://security.netapp.com/advisory/ntap-20210507-0007/

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