Detections
Analytics

Echo: unbound: security update to 1.26.2

medium Tenable Cloud Security Plugin ID 476923

Description

There are packages installed that are affected by a vulnerability referenced in the following CVE:

 - When NLnet Labs Unbound up to and including version 1.26.1 is configured with both a root trust anchor and
 an additional 'trust-anchor:' for an island-of-security zone whose parent is provably insecure under the
 root chain, a malicious actor who can deliver one forged NXDOMAIN response for a name inside the island,
 with the NSEC/SOA RRSIG 'SignerName' set to the insecure parent, tricks Unbound's validator to use the
 root trust anchor instead, and consecutively the insecure parent, thus causing that record to be treated
 as insecure and denying existence for records in the trust island. (CVE-2026-50106)

Solution

Update the unbound library and its related packages to version 1.26.2 or later.

See Also

https://advisory.echohq.com/cve/CVE-2026-50106

Plugin Details

Severity: Medium

ID: 476923

Version: Revision 1.1

Type: Local

Published: 10/23/2026

Updated: 10/23/2026

Risk Information

VPR

Risk Factor: Low

Score: 3.5

Percentile: 51.44

CVSS v2

Risk Factor: Medium

Base Score: 6.1

Temporal Score: 4.5

Vector: CVSS2#AV:N/AC:H/Au:N/C:N/I:P/A:C

CVSS Score Source: CVE-2026-50106

CVSS v3

Risk Factor: Medium

Base Score: 6.5

Temporal Score: 5.7

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

Exploit Ease: No known exploits are available

Patch Publication Date: 10/21/2026

Vulnerability Publication Date: 10/21/2026

Reference Information

CVE: CVE-2026-50106

IAVA: 2026-A-1194