CVE-2023-26595

Denial-of-service (DoS) vulnerability in Message of Cybozu Garoon 4.10.0 to 5.9.2 allows a remote authenticated attacker to cause a denial of service condition.

Published: 2023-05-23 Last update: 2025-01-28 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2023-26595 is rated Moderate Risk (45.9/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 0.35%). Mandatory action: 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-2023-26595

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 2026-05-24 0.58% 0.35% -0.23%
2 2026-03-19 0.55% 0.58% +0.04%
3 2026-02-15 0.55%

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-26595

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/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:L)
A normal user session is enough; they don’t have to be admin.
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.
2.8 3.6 [email protected]
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
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:L)
A normal user session is enough; they don’t have to be admin.
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.
1.8 3.6 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2023-26595

Affected software / configurations for CVE-2023-26595

Vendor Product Version Raw CPE
cybozu garoon >= 4.10.0, <= 5.9.2 cpe:2.3:a:cybozu:garoon:*:*:*:*:*:*:*:*

References for CVE-2023-26595

URL Tags
https://cs.cybozu.co.jp/2023/007698.html Vendor Advisory
https://jvn.jp/en/jp/JVN41694426/ Third Party Advisory
cvelogic Threat Intelligence