Detections
Analytics

Echo: unbound: security update to 1.25.2

medium Tenable Cloud Security Plugin ID 455572

Description

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

 - In NLnet Labs Unbound 1.6.2 up to and including 1.25.1, when Unbound is configured with the 'respip'
 module in front of the validator together with a 'response-ip' redirect rule or an RPZ file with an RPZ-IP
 trigger, the rewriting handler does not check the security status of the upstream answer and can instead
 rewrite a BOGUS A/AAAA answer to point to an operator's configured IP. If the validator finds an expired
 or otherwise invalid RRSIG on an answer whose A record falls within a 'response-ip'/RPZ configuration, the
 answer is still rewritten and given a hard coded security level of INSECURE. This results in the client
 receiving an INSECURE NOERROR reply rewritten by the operator's configured IP. A malicious actor can
 exploit the possible poisonous effect by spoofing a BOGUS A/AAAA answer that falls inside the operator's
 configured subnet rewrites. Such DNSSEC protected answers are then insecurely redirected to the operator's
 configured target. (CVE-2026-50243)

Solution

Update the unbound library and its related packages to version 1.25.2 or later.

See Also

https://advisory.echohq.com/cve/CVE-2026-50243

Plugin Details

Severity: Medium

ID: 455572

Version: Revision 1.2

Type: Local

Published: 10/1/2026

Updated: 10/2/2026

Supported Sensors: Tenable Cloud Security, Tenable Self-Hosted Container Security

Risk Information

VPR

Risk Factor: Low

Score: 1.2

Percentile: 0.01

CVSS v2

Risk Factor: Low

Base Score: 2.6

Temporal Score: 1.9

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

CVSS Score Source: CVE-2026-50243

CVSS v3

Risk Factor: Low

Base Score: 3.7

Temporal Score: 3.2

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

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

CVSS v4

Risk Factor: Medium

Base Score: 6.3

Threat Score: 1.7

Threat Vector: CVSS:4.0/E:U

Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N

Vulnerability Information

Exploit Ease: No known exploits are available

Patch Publication Date: 7/23/2026

Vulnerability Publication Date: 7/22/2026

Reference Information

CVE: CVE-2026-50243