ISC BIND 9 9.20.09.20.20 Memory Leak via Crafted Domain
CVE-2026-3104 Published on March 25, 2026
Memory leak in code preparing DNSSEC proofs of non-existence
A specially crafted domain can be used to cause a memory leak in a BIND resolver simply by querying this domain.
This issue affects BIND 9 versions 9.20.0 through 9.20.20, 9.21.0 through 9.21.19, and 9.20.9-S1 through 9.20.20-S1.
BIND 9 versions 9.18.0 through 9.18.46 and 9.18.11-S1 through 9.18.46-S1 are NOT affected.
Vulnerability Analysis
CVE-2026-3104 is exploitable with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity, and a high impact on availability.
Weakness Type
Missing Release of Resource after Effective Lifetime
The software does not release a resource after its effective lifetime has ended, i.e., after the resource is no longer needed. When a resource is not released after use, it can allow attackers to cause a denial of service by causing the allocation of resources without triggering their release. Frequently-affected resources include memory, CPU, disk space, power or battery, etc.
Products Associated with CVE-2026-3104
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Affected Versions
ISC BIND 9:- Version 9.20.0, <= 9.20.20 is affected.
- Version 9.21.0, <= 9.21.19 is affected.
- Version 9.20.9-S1, <= 9.20.20-S1 is affected.
- Version 9.18.0, <= 9.18.46 is unaffected.
- Version 9.18.11-S1, <= 9.18.46-S1 is unaffected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.