# CVE-2024-23684: upokecenter CBOR Denial of Service

Status: published. Published: 2024-01-19. Updated: 2026-11-08.

Inefficient algorithmic complexity in DecodeFromBytes function in com.upokecenter.cbor Java implementation of Concise Binary Object Representation (CBOR) versions 4.0.0 to 4.5.1 allows an attacker to cause a denial of service by passing a maliciously crafted input. Depending on an application's use of this library, this may be a remote attacker.

## Remediation

- fix: com.upokecenter:cbor (Maven): OSV reports a fixed version 4.5.1. Check the advisory for supported release branches. (source: OSV GHSA-fj2w-wfgv-mwq6) — https://github.com/advisories/GHSA-fj2w-wfgv-mwq6

## Affected products and versions

-  /  (com.upokecenter:cbor): ≥ 4.0.0; < 4.5.1 (affected, maven). Source: CNA: VulnCheck
-  / com.upokecenter:cbor (com.upokecenter:cbor): 4.0.0 (affected, Maven); 4.0.1 (affected, Maven); 4.1.0 (affected, Maven); 4.1.1 (affected, Maven); 4.1.3 (affected, Maven); 4.2.0 (affected, Maven); 4.3.0 (affected, Maven); 4.4.0 (affected, Maven); 4.4.1 (affected, Maven); 4.4.2 (affected, Maven); 4.4.3 (affected, Maven); 4.4.4 (affected, Maven); 4.5 (affected, Maven); Ecosystem version events: introduced 4.0.0; fixed 4.5.1. Source: OSV GHSA-fj2w-wfgv-mwq6

## Severity and prioritization

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: ADP: CISA-ADP

- CISA KEV: No listing in collected sources

- EPSS: 0.92% as of 2026-11-08; percentile 60.52%

- SSVC: exploitation none; automatable no; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-407

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://github.com/peteroupc/CBOR-Java/security/advisories/GHSA-fj2w-wfgv-mwq6 (CNA: VulnCheck; vendor-advisory)

- https://github.com/advisories/GHSA-fj2w-wfgv-mwq6 (CNA: VulnCheck; vendor-advisory)

- https://vulncheck.com/advisories/vc-advisory-GHSA-fj2w-wfgv-mwq6 (CNA: VulnCheck; third-party-advisory)

- https://github.com/peteroupc/CBOR-Java/security/advisories/GHSA-fj2w-wfgv-mwq6 (ADP: CVE; vendor-advisory, x_transferred)

- https://github.com/advisories/GHSA-fj2w-wfgv-mwq6 (ADP: CVE; third-party-advisory, x_transferred)

- https://vulncheck.com/advisories/vc-advisory-GHSA-fj2w-wfgv-mwq6 (ADP: CVE; third-party-advisory, x_transferred)

- https://github.com/advisories/GHSA-fj2w-wfgv-mwq6 (OSV / GitHub Security Advisories; advisory)

- https://osv.dev/vulnerability/GHSA-fj2w-wfgv-mwq6 (OSV / GitHub Security Advisories; osv)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2024-23684; retrieved 2026-11-08; source updated 2026-11-08

- OSV / GitHub Security Advisories: https://osv.dev/vulnerability/GHSA-fj2w-wfgv-mwq6; retrieved 2026-11-08; source updated 2026-07-08

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2024-23684; retrieved 2026-11-08; source updated Not reported

Revision: 2da959761ddcd44b670d69964c1c456ed7dafe9c4794c699d8f4524cad55fa49

Canonical: https://y2.dev/cve/CVE-2024-23684

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