CVE-2023-29451 | Denial of service caused by a bug in the JSON parser

Specially crafted string can cause a buffer overrun in the JSON parser library leading to a crash of the Zabbix Server or a Zabbix Proxy.

Published: 2023-07-13 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-29451 is rated Low Risk (28.5/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.10%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

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-2023-29451

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 2025-11-21 0.34% 0.10% -0.24%
2 2025-11-18 0.10% 0.34% +0.24%
3 2025-04-15 — 0.10% —

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-29451

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.7 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:L 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:H)
They need powerful rights—admin, root, or similar—before this pays off.
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:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 1.2 3.4 [email protected]
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-2023-29451

OS Trackers for CVE-2023-29451

vendor priority summary link
debian unimportant CVE-2023-29451 unimportant priority: Debian including 1 source packages (zabbix), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 4, open 1. https://security-tracker.debian.org/tracker/CVE-2023-29451
suse medium CVE-2023-29451 severity moderate: SUSE including 2 source package names (zabbix, zabbix-agent), 16 product×package rows across 10 product lines (SUSE Linux Enterprise High Performance Computing 12 SP5, SUSE Linux Enterprise Server 12 SP4-ESPOS, … (10 product lines)): Known Not Affected 16. https://www.suse.com/security/cve/CVE-2023-29451/
ubuntu medium CVE-2023-29451 medium priority: Ubuntu including 1 source packages (zabbix), 10 status rows across 10 suites (bionic, focal, jammy, kinetic, lunar, mantic, noble, trusty, upstream, xenial): not-affected 5, ignored 3, DNE 1, released 1. https://ubuntu.com/security/CVE-2023-29451

Affected software / configurations for CVE-2023-29451

Vendor Product Version Raw CPE
zabbix zabbix <= 6.0.14 cpe:2.3:a:zabbix:zabbix:*:*:*:*:*:*:*:*
zabbix zabbix >= 6.4.2, <= 6.4.4 cpe:2.3:a:zabbix:zabbix:*:*:*:*:*:*:*:*
zabbix zabbix 6.4.0 cpe:2.3:a:zabbix:zabbix:6.4.0:alpha1:*:*:*:*:*:*
zabbix zabbix 6.4.0 cpe:2.3:a:zabbix:zabbix:6.4.0:beta1:*:*:*:*:*:*
zabbix zabbix 6.4.0 cpe:2.3:a:zabbix:zabbix:6.4.0:beta2:*:*:*:*:*:*
zabbix zabbix 6.4.0 cpe:2.3:a:zabbix:zabbix:6.4.0:beta3:*:*:*:*:*:*
zabbix zabbix 6.4.0 cpe:2.3:a:zabbix:zabbix:6.4.0:beta4:*:*:*:*:*:*
zabbix zabbix 6.4.0 cpe:2.3:a:zabbix:zabbix:6.4.0:beta5:*:*:*:*:*:*
zabbix zabbix 6.4.0 cpe:2.3:a:zabbix:zabbix:6.4.0:beta6:*:*:*:*:*:*
zabbix zabbix 6.4.0 cpe:2.3:a:zabbix:zabbix:6.4.0:rc2:*:*:*:*:*:*
zabbix zabbix 6.4.0 cpe:2.3:a:zabbix:zabbix:6.4.0:rc3:*:*:*:*:*:*
zabbix zabbix 6.4.0 cpe:2.3:a:zabbix:zabbix:6.4.0:rc4:*:*:*:*:*:*

References for CVE-2023-29451

cvelogic Threat Intelligence