CVE-2026-109125: unbound security update
Affects unboundSource GCVE Database
Mentioned vulnerabilities
Not known to be exploited · CVSS 5.3 Medium : upgrade to 1.17.1-25.oe2403sp1 when convenient.
Data as of 4 Nov 2026, 16:47 UTC
Thin evidence
One scorer or none| CNA (NLnet Labs) | CVSS 3.1 | 5.3 |
|---|
- Patch
- Available – fixed in 1.17.1-25.oe2403sp1
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:NExploitation evidence
Disclosed: evidence found.
CVE published 21 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 4 Nov 2026.
What to do
Upgrade unbound to 1.17.1-25.oe2403sp1.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
openEuler 24.03-LTS-SP1unboundpkg:rpm/openEuler/unbound&distro=openEuler-24.03-LTS-SP1Other threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A security update fixing these vulnerabilities is available in NLnet Labs Unbound version 1.17.1-25.oe2403sp1. Users should upgrade to this fixed version to remediate the issues. No additional mitigations are indicated or required if the update is applied. For configurations using 'unwanted-reply-threshold', consider reverting to default settings to reduce exposure until patched.
Description
Multiple security vulnerabilities affect NLnet Labs Unbound up to and including version 1.26.1. These include a cache-level side-channel vulnerability that can leak upstream source port information under specific configurations, DNSSEC validation bypasses that can cause trust islands to be treated as insecure, and a performance degradation issue via chained compression pointers. These flaws can lead to cache poisoning, denial of DNS record existence, and degraded resolver performance. A fix is available in version 1.17.1-25.oe2403sp1.
References
- openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-4733 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-109125 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-35501 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-50106 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-96405 (opens in a new tab)