CVE-2023-2829 | Malformed NSEC records can cause named to terminate unexpectedly when synth-from-dnssec is enabled

A `named` instance configured to run as a DNSSEC-validating recursive resolver with the Aggressive Use of DNSSEC-Validated Cache (RFC 8198) option (`synth-from-dnssec`) enabled can be remotely terminated using a zone with a malformed NSEC record. This issue affects BIND 9 versions 9.16.8-S1 through 9.16.41-S1 and 9.18.11-S1 through 9.18.15-S1.

Published: 2023-06-21 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-2829 is rated Moderate Risk (49.6/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.92%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-2829

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-22 0.79% 0.92% +0.13%
2 2026-06-15 0.07% 0.79% +0.72%
3 2025-11-21 — 0.07% —

Full EPSS history (11 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-2829

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2023-2829

OS Trackers for CVE-2023-2829

vendor priority summary link
alpine high CVE-2023-2829: 1 source package rows (bind); 50 state rows across 5 repos (3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 0, open 50. https://security.alpinelinux.org/vuln/CVE-2023-2829
debian unimportant CVE-2023-2829 unimportant priority: Debian including 1 source packages (bind9), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2023-2829
redhat high — https://access.redhat.com/security/cve/CVE-2023-2829
suse high CVE-2023-2829 severity important: SUSE including 32 source package names (bind, bind-chrootenv, …), 369 product×package rows across 38 product lines (SUSE CaaS Platform 4.0, SUSE Enterprise Storage 7, … (38 product lines)): Known Not Affected 369. https://www.suse.com/security/cve/CVE-2023-2829/
ubuntu medium CVE-2023-2829 medium priority: Ubuntu including 2 source packages (bind9, isc-dhcp), 16 status rows across 8 suites (bionic, focal, jammy, kinetic, lunar, trusty, upstream, xenial): not-affected 15, needs-triage 1. https://ubuntu.com/security/CVE-2023-2829

Affected software / configurations for CVE-2023-2829

Vendor Product Version Raw CPE
isc bind >= 9.16.8, <= 9.16.41 cpe:2.3:a:isc:bind:*:*:*:*:supported_preview:*:*:*
isc bind >= 9.18.11, <= 9.18.15 cpe:2.3:a:isc:bind:*:*:*:*:supported_preview:*:*:*
netapp active_iq_unified_manager — cpe:2.3:a:netapp:active_iq_unified_manager:-:*:*:*:*:vmware_vsphere:*:*
netapp h500s_firmware — cpe:2.3:o:netapp:h500s_firmware:-:*:*:*:*:*:*:*
netapp h700s_firmware — cpe:2.3:o:netapp:h700s_firmware:-:*:*:*:*:*:*:*
netapp h410s_firmware — cpe:2.3:o:netapp:h410s_firmware:-:*:*:*:*:*:*:*
netapp h410c_firmware — cpe:2.3:o:netapp:h410c_firmware:-:*:*:*:*:*:*:*
netapp h300s_firmware — cpe:2.3:o:netapp:h300s_firmware:-:*:*:*:*:*:*:*

References for CVE-2023-2829

cvelogic Threat Intelligence