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CVE-2023-25136

6.5
MEDIUMCVSS v3.1 Base Score
88.33%
HIGH RiskEPSS (100th percentile)

OpenSSH server (sshd) 9.1 introduced a double-free vulnerability during options.kex_algorithms handling. This is fixed in OpenSSH 9.2. The double free can be leveraged, by an unauthenticated remote attacker in the default configuration, to jump to any location in the sshd address space. One third-party report states "remote code execution is theoretically possible."

Published: 2/3/2023
Modified: 5/28/2026
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Vulnerability Summary

CVSS v3 Score

6.5MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H

EPSS Score (Exploitation Probability)

88.33%HIGH Exploitation Risk
100th percentile

This vulnerability has a 88.33% probability of being exploited in the next 30 days, ranking higher than 100% of all scored CVEs.

CWE Classification

Related Vulnerabilities

Same Weakness Type(CWE-415)

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An issue was discovered in SchedMD Slurm 22.05.x, 23.02.x, and 23.11.x. Because of a double free, attackers can cause a denial of service or possibly execute arbitrary code. The fixed versions are 22.05.11, 23.02.7, and 23.11.1.

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CVE-2023-35784CRITICAL 9.8

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6/16/2023
CVE-2022-40515HIGH 7.3

Memory corruption in Video due to double free while playing 3gp clip with invalid metadata atoms.

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