Root escalation via restricted shell bypass
Published Jul 19, 2021 · Updated Sep 16, 2024
Privilege escalation in IBM Hardware Management Console 9.1.910.0 and 9.2.950.0 allows local users to gain root access through a restricted shell. The hmcbash environment leaves sed execution escapes available; sed can run commands, reach an unrestricted bash, and invoke the setuid asmmenu wrapper with an unsanitized environment to execute a root shell. The attack requires a local HMC account, and successful exploitation grants complete control of the console with confidentiality, integrity, and availability impact.
Summary
What happened
Privilege escalation in IBM Hardware Management Console 9.1.910.0 and 9.2.950.0 allows local users to gain root access through a restricted shell. The hmcbash environment leaves sed execution escapes available; sed can run commands, reach an unrestricted bash, and invoke the setuid asmmenu wrapper with an unsanitized environment to execute a root shell. The attack requires a local HMC account, and successful exploitation grants complete control of the console with confidentiality, integrity, and availability impact.
The record
- CVE
- CVE-2021-29707
- Published
- Jul 19, 2021
- Updated
- Sep 16, 2024
- Vendor
- IBM
- Product
- IBM Hardware Management Console
- Classifications
- CWE-269, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 19, 2021CVE publishedPublication date reported by the CVE source.
- Sep 16, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=9.1.910.0
- Affected versionversion=9.2.950.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- IBM HMC Exploit CVE-2021-29707proof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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