CVE-2023-4043 | Parsson DoS when parsing numbers from untrusted sources

Exp

In Eclipse Parsson before versions 1.1.4 and 1.0.5, Parsing JSON from untrusted sources can lead malicious actors to exploit the fact that the built-in support for parsing numbers with large scale in Java has a number of edge cases where the input text of a number can lead to much larger processing time than one would expect. To mitigate the risk, parsson put in place a size limit for the numbers as well as their scale.

Published: 2023-11-03 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2023-4043 is rated Exploit Available (56.9/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.76%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

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

Public exploit references (Exploit-DB) for CVE-2023-4043

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2023-4043

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 2026-06-15 0.15% 0.76% +0.61%
2 2025-12-06 0.11% 0.15% +0.04%
3 2025-11-25 0.11%

Full EPSS history (13 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-4043

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.9 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
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.
2.2 3.6 [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-2023-4043

GitHub Security Advisory for CVE-2023-4043

GHSA-g8p6-p27c-52fx · Severity: medium · Ecosystem: maven — Eclipse Parsson Denial of Service vulnerability

OS Trackers for CVE-2023-4043

vendor priority summary link
redhat high https://access.redhat.com/security/cve/CVE-2023-4043

Affected software / configurations for CVE-2023-4043

Vendor Product Version Raw CPE
eclipse parsson < 1.0.5 cpe:2.3:a:eclipse:parsson:*:*:*:*:*:*:*:*
eclipse parsson >= 1.1.0, < 1.1.4 cpe:2.3:a:eclipse:parsson:*:*:*:*:*:*:*:*

References for CVE-2023-4043

cvelogic Threat Intelligence