CSIRTS // UNIFIED SECURITY ADVISORY FEEDSYS ● ONLINE · POWERED BY INTELFUSIONS.COM

CVE-2026-52863: In NLnet Labs Unbound 1.25.0 up to and including 1.25.1, a fix that makes the 'respip' and 'dns64' modules work together, creates a shallow copy of the view name in effect that cou

mediumCVSS 5.9CVE-2026-52863
In NLnet Labs Unbound 1.25.0 up to and including 1.25.1, a fix that makes the 'respip' and 'dns64' modules work together, creates a shallow copy of the view name in effect that could lead to memory corruption if the owner of the original view name is jostled out when Unbound is under pressure. Unbound needs to be configured with one of 'respip'/'rpz' modules, together with a module that can attach subqueries (respip CNAME redirection, dns64, subnetcache) and a configured 'access-control-view' while Unbound is under pressure so that joslte logic kicks in and starts dropping slow queries. The subquery is getting a shallow copy of the view name and if the super query which owns the view name is jostled out, memory corruption can occur. Likelihood of a crash is low, since it relies heavily on the underlying memory allocator and the memory layout. Debug memory builds (e.g., ASAN) that catch the free terminate the server.

Details

Source
NVD Recent CVEs (US · database · site)
Severity
medium — CVSS 5.9
Published
2026-07-22
Last updated
2026-07-24
Exploitation
Not in CISA KEV at last sync

Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-52863

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Referenced CVEs

CVECSIRTS overviewExternal
CVE-2026-52863coverage & exploitation statusNVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

Recent advisories for In NLnet Labs

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

More from NVD Recent CVEs