CVE-2025-59043 | OpenBao vulnerable to denial of service via malicious JSON request processing

OpenBao is an open source identity-based secrets management system. In OpenBao versions prior to 2.4.1, JSON objects after decoding may use significantly more memory than their serialized version. It is possible to craft a JSON payload to maximize the factor between serialized memory usage and deserialized memory usage, similar to a zip bomb, with factors reaching approximately 35. This can be used to circumvent the max_request_size configuration parameter which is intended to protect against denial of service attacks. The request body is parsed into a map very early in the request handling chain before authentication, which means an unauthenticated attacker can send a specifically crafted JSON object and cause an out-of-memory crash. Additionally, for requests with large numbers of strings, the audit subsystem can consume large quantities of CPU. The vulnerability is fixed in version 2.4.1.

Published: 2025-10-17 Last update: 2025-10-24 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-59043 is rated Moderate Risk (44.2/100): CVSS High severity, with low exploitation likelihood (EPSS 0.19%). 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-2025-59043

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 2026-03-27 0.14% 0.19% +0.05%
2 2026-03-15 0.22% 0.14% -0.08%
3 2026-02-16 — 0.22% —

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-59043

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-2025-59043

GitHub Security Advisory for CVE-2025-59043

GHSA-g46h-2rq9-gw5m · Severity: high · Ecosystem: go — OpenBao has potential Denial of Service vulnerability when processing malicious unauthenticated JSON requests

OS Trackers for CVE-2025-59043

vendor priority summary link
alpine — CVE-2025-59043: 1 source package rows (openbao); 23 state rows across 2 repos (3.22-community, edge-community); fixed 2, open 21. https://security.alpinelinux.org/vuln/CVE-2025-59043

Affected software / configurations for CVE-2025-59043

Vendor Product Version Raw CPE
openbao openbao < 2.4.1 cpe:2.3:a:openbao:openbao:*:*:*:*:*:*:*:*

References for CVE-2025-59043

cvelogic Threat Intelligence