CVE-2026-109125: unbound security update
Affects unboundSource GCVE Database
Mentioned vulnerabilities
Not known to be exploited · CVSS 5.3 Medium : upgrade to 1.13.2-31.oe2203sp4 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 1.13.2-31.oe2203sp4
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 1.13.2-31.oe2203sp4.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
openEuler 22.03-LTS-SP4unboundpkg:rpm/openEuler/unbound&distro=openEuler-22.03-LTS-SP4Other 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 Unbound version 1.13.2-31.oe2203sp4. Users should upgrade to this fixed version to mitigate the risks. The cache side-channel attack requires non-default configuration ('unwanted-reply-threshold' > 0), so default configurations are not vulnerable to this attack vector. No other specific mitigations are indicated by the vendor advisory.
Description
Multiple 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 non-default configurations, DNSSEC validation bypasses that can cause trust islands to be treated as insecure, and a resource exhaustion issue from chained compression pointers that can degrade performance. These issues can facilitate cache poisoning, denial of existence for DNS records, and performance degradation. A fix is available in version 1.13.2-31.oe2203sp4.
References
- openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-4732 (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)