CVE-2020-10030

CVE-2020-10030 is a high-severity vulnerability in Powerdns Recursor with a CVSS 3.x base score of 8.8. Its EPSS exploit-prediction score of 24% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-125.

Key facts

Description

An issue has been found in PowerDNS Recursor 4.1.0 up to and including 4.3.0. It allows an attacker (with enough privileges to change the system's hostname) to cause disclosure of uninitialized memory content via a stack-based out-of-bounds read. It only occurs on systems where gethostname() does not have '\0' termination of the returned string if the hostname is larger than the supplied buffer. (Linux systems are not affected because the buffer is always large enough. OpenBSD systems are not affected because the returned hostname always has '\0' termination.) Under some conditions, this issue can lead to the writing of one '\0' byte out-of-bounds on the stack, causing a denial of service or possibly arbitrary code execution.

Frequently asked questions

What is CVE-2020-10030?
An issue has been found in PowerDNS Recursor 4.1.0 up to and including 4.3.0. It allows an attacker (with enough privileges to change the system's hostname) to cause disclosure of uninitialized memory content via a stack-based out-of-bounds read. It only occurs on systems where gethostname() does not have '\0' termination of the returned string if the hostname is larger than the supplied buffer. (Linux systems are not affected because the buffer is always large enough. OpenBSD systems are not affected because the returned hostname always has '\0' termination.) Under some conditions, this issue can lead to the writing of one '\0' byte out-of-bounds on the stack, causing a denial of service or possibly arbitrary code execution.
How severe is CVE-2020-10030?
CVE-2020-10030 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-10030 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 24% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-10030?
CVE-2020-10030 affects Powerdns Recursor. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-10030?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2020-10030 published?
CVE-2020-10030 was published on 2020-05-19 and last updated on 2026-06-17.

References

Affected products (1)

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