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Fedora 44 : unbound (2026-e495bd59ef)

high Nessus Plugin ID 330825

Synopsis

The remote Fedora host is missing one or more security updates.

Description

The remote Fedora 44 host has a package installed that is affected by multiple vulnerabilities as referenced in the FEDORA-2026-e495bd59ef advisory.

 Update to 1.25.2 (rhbz#2506061)

 Security fixes:

 - Fix CVE-2026-14586, Assertion in libngtcp2 when under pressure in high concurrency DNS-over-QUIC environments. Thanks to Kunta Chu, Kaihua Wang, and Jianjun Chen from Tsinghua University, for the report.
 - Fix CVE-2026-32665, Remote DNS-over-QUIC denial of service due to `quic-size` budget bypass. Thanks to N0zoM1z0 (https://github.com/N0zoM1z0) for the report. In addition, thanks to Kunta Chu, Kaihua Wang, and Jianjun Chen from Tsinghua University, for also reporting this issue. In addition, thanks to Qifan Zhang, Palo Alto Networks, for also reporting this issue. In addition, thanks to Xuanchao Xie, for also reporting this issue.
 - Fix CVE-2026-40691, Packet of death for DNSCrypt over TCP. Thanks to Qifan Zhang, Palo Alto Networks, for the report. In addition, thanks to Trung Nguyen (@everping) of CyStack, for also reporting this issue.
 - Fix CVE-2026-41637, Degradation of resolution service from improperly accounted client-terminated DNS- over-QUIC queries. Thanks to Qifan Zhang, Palo Alto Networks, for the report.
 - Fix CVE-2026-42955, Extra fix for CVE-2026-40622 to also clamp the TTL of A/AAAA records disallowing a one-time 'ghost domain' delegation renewal via glue records. Thanks to Qifan Zhang, Palo Alto Networks, for the report.
 - Fix CVE-2026-44621, Libunbound applications configured with 'unwanted-reply-threshold' could eventually be abruptly terminated. Thanks to Qifan Zhang, Palo Alto Networks, for the report.
 - Fix CVE-2026-44687, Off-by-one error in 'harden-below-nxdomain' logic can shadow a stub/forward zone by a legitimate parent's NXDOMAIN. Thanks to Qifan Zhang, Palo Alto Networks, for the report.
 - Fix CVE-2026-44690, Cross-zone wildcard cache poisoning via RRSIG.labels manipulation. Thanks to Qifan Zhang, Palo Alto Networks, for the report.
 - Fix CVE-2026-46582, A wildcard replay, as another piece of data, triggers poisoning in the serve expired reply path. Thanks to Qifan Zhang, Palo Alto Networks, for the report.
 - Fix CVE-2026-50045, 'max-global-quota' reset by DNSSEC validation restarts. Thanks to Kunjie Shang, University of Science and Technology of China, for the report.
 - Fix CVE-2026-50046, Possible heap use-after-free in an error path when a DoT forwarded query is jostled out. Thanks to Qifan Zhang, Palo Alto Networks, for the report.
 - Fix CVE-2026-50243, 'response-ip'/'rpz' can rewrite BOGUS answers instead of returning SERVFAIL. Thanks to Qifan Zhang, Palo Alto Networks, for the report.
 - Fix CVE-2026-50248, BOGUS configured primary hostname accepted for XFR in auth/rpz zones. Thanks to Qifan Zhang, Palo Alto Networks, for the report.
 - Fix CVE-2026-50251, Attacker supplied `0.0.0.0`/`::` glue triggers defensive full-cache flush. Thanks to Qifan Zhang, Palo Alto Networks, for the report.
 - Fix CVE-2026-50252, Possible cache poisoning attack by mapping source port population per thread. Thanks to Inbal Schussheim and Amit Klein, Hebrew University, for the report.
 - Fix CVE-2026-52863, Memory corruption could lead to crash and denial of service. Thanks to Qifan Zhang, Palo Alto Networks, for the report.
 - Fix CVE-2026-54478, DNS Cookie bypass when combined with proxy-protocol use. Thanks to Qifan Zhang, Palo Alto Networks, for the report.
 - Fix CVE-2026-55708, Privacy/configuration issue when adding local data in views through 'unbound- control'. Thanks to Qifan Zhang, Palo Alto Networks, for the report.
 - Fix CVE-2026-55717, 'serve-expired-client-timeout' and 'response-ip' CNAME redirect could lead to a crash. Thanks to Qifan Zhang, Palo Alto Networks, for the report. In addition, thanks to Xin Wang, Jiapeng Li, and Jiajia Liu, Northwestern Polytechnical University, for also reporting this issue.
 - Fix CVE-2026-55973, 'dns-error-reporting: yes' leads to stack buffer overflow. Thanks to Qifan Zhang, Palo Alto Networks, for the report.
 - Fix CVE-2026-55990, Packet of death for a DNSCrypt misconfigured Unbound. Thanks to Qifan Zhang, Palo Alto Networks, for the report.
 - Fix CVE-2026-55991, Remote DNS-over-QUIC (DoQ) flow-control assertion failure in libngtcp2. Thanks to Qifan Zhang, Palo Alto Networks, for the report. In addition, thanks to Xuanchao Xie, for also reporting this issue.
 - Fix CVE-2026-56416, Possible heap buffer overflow when validator canonicalizes RDATA that contains domain name. Thanks to Qifan Zhang, Palo Alto Networks, for the report.
 - Fix CVE-2026-56444, Degradation of resolution service when 'discard-timeout' and 'serve-expired-client- timeout' are combined in unusual configuration. Thanks to Qifan Zhang, Palo Alto Networks, for the report.
 In addition, thanks to Xin Wang, Jiapeng Li, and Jiajia Liu, Northwestern Polytechnical University, for also reporting this issue. In addition, thanks to Haruki Oyama (Waseda University), for also reporting this issue.

 Source: https://nlnetlabs.nl/projects/unbound/download/#unbound-1-25-2



Tenable has extracted the preceding description block directly from the Fedora security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Update the affected unbound package.

See Also

https://bodhi.fedoraproject.org/updates/FEDORA-2026-e495bd59ef

Plugin Details

Severity: High

ID: 330825

File Name: fedora_2026-e495bd59ef.nasl

Version: 1.1

Type: Local

Agent: unix

Published: 7/30/2026

Updated: 7/30/2026

Supported Sensors: Continuous Assessment, Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 6.8

Percentile: 96.83

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

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

CVSS Score Source: CVE-2026-50252

CVSS v3

Risk Factor: Critical

Base Score: 9.3

Temporal Score: 8.1

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

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

CVSS v4

Risk Factor: High

Base Score: 8.7

Threat Score: 6.6

Threat Vector: CVSS:4.0/E:U

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

CVSS Score Source: CVE-2026-41292

Vulnerability Information

CPE: cpe:/o:fedoraproject:fedora:44, p-cpe:/a:fedoraproject:fedora:unbound

Required KB Items: Host/local_checks_enabled, Host/RedHat/release, Host/RedHat/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 7/27/2026

Vulnerability Publication Date: 5/20/2026

Reference Information

CVE: CVE-2026-14586, CVE-2026-32665, CVE-2026-40622, CVE-2026-40691, CVE-2026-41292, CVE-2026-41637, CVE-2026-42534, CVE-2026-42955, CVE-2026-44390, CVE-2026-44621, CVE-2026-44687, CVE-2026-44690, CVE-2026-46582, CVE-2026-50045, CVE-2026-50046, CVE-2026-50243, CVE-2026-50248, CVE-2026-50251, CVE-2026-50252, CVE-2026-52863, CVE-2026-54478, CVE-2026-55708, CVE-2026-55717, CVE-2026-55973, CVE-2026-55990, CVE-2026-55991, CVE-2026-56416, CVE-2026-56444