CVE-2011-0539

7.5 HIGH

The key_certify function in usr.bin/ssh/key.c in OpenSSH 5.6 and 5.7, when generating legacy certificates using the -t command-line optio...

Published: 2011-02-10 · Last updated: 2026-05-29

Severity and scoring

CVSS: 7.5 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CWE: CWE-264, CWE-457

Affected products

Vendor	Product
openbsd	openssh

Description

The key_certify function in usr.bin/ssh/key.c in OpenSSH 5.6 and 5.7, when generating legacy certificates using the -t command-line option in ssh-keygen, does not initialize the nonce field, which might allow remote attackers to obtain sensitive stack memory contents or make it easier to conduct hash collision attacks.

Source: NVD

References

[NVD]https://nvd.nist.gov/vuln/detail/CVE-2011-0539
[Other]http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c02794777
[Other]http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10673
[Vendor advisory]http://secunia.com/advisories/43181
[Other]http://secunia.com/advisories/44269
[Patch]http://www.openssh.com/txt/legacy-cert.adv
[Other]http://www.openwall.com/lists/oss-security/2011/02/04/2
[Other]http://www.securityfocus.com/bid/46155
[Other]http://www.securitytracker.com/id?1025028
[Vendor advisory]http://www.vupen.com/english/advisories/2011/0284
[Other]https://exchange.xforce.ibmcloud.com/vulnerabilities/65163
[Other]http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c02794777
[Other]http://kb.juniper.net/InfoCenter/index?page=content&id=JSA10673
[Vendor advisory]http://secunia.com/advisories/43181
[Other]http://secunia.com/advisories/44269
[Patch]http://www.openssh.com/txt/legacy-cert.adv
[Other]http://www.openwall.com/lists/oss-security/2011/02/04/2
[Other]http://www.securityfocus.com/bid/46155
[Other]http://www.securitytracker.com/id?1025028
[Vendor advisory]http://www.vupen.com/english/advisories/2011/0284
[Other]https://exchange.xforce.ibmcloud.com/vulnerabilities/65163

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