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This CVE record has been marked for NVD enrichment efforts.
Description
A race condition vulnerability was discovered in how signals are handled by OpenSSH's server (sshd). If a remote attacker does not authenticate within a set time period, then sshd's SIGALRM handler is called asynchronously. However, this signal handler calls various functions that are not async-signal-safe, for example, syslog(). As a consequence of a successful attack, in the worst case scenario, an attacker may be able to perform a remote code execution (RCE) as an unprivileged user running the sshd server.
Metrics
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Red Hat, Inc. http://www.openwall.com/lists/oss-security/2024/07/08/2
Removed
Reference
Red Hat, Inc. http://www.openwall.com/lists/oss-security/2024/07/09/2
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Reference
Red Hat, Inc. http://www.openwall.com/lists/oss-security/2024/07/09/5
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Red Hat, Inc. http://www.openwall.com/lists/oss-security/2024/07/10/1
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Red Hat, Inc. http://www.openwall.com/lists/oss-security/2024/07/10/2
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Reference
Red Hat, Inc. https://almalinux.org/blog/2024-07-09-cve-2024-6409/
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Reference
Red Hat, Inc. https://bugzilla.suse.com/show_bug.cgi?id=1227217
Removed
Reference
Red Hat, Inc. https://explore.alas.aws.amazon.com/CVE-2024-6409.html
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Reference
Red Hat, Inc. https://github.com/openela-main/openssh/commit/c00da7741d42029e49047dd89e266d91dcfbffa0
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Reference
Red Hat, Inc. https://security-tracker.debian.org/tracker/CVE-2024-6409
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Reference
Red Hat, Inc. https://security.netapp.com/advisory/ntap-20240712-0003/
Removed
Reference
Red Hat, Inc. https://sig-security.rocky.page/issues/CVE-2024-6409/
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Reference
Red Hat, Inc. https://ubuntu.com/security/CVE-2024-6409
Removed
Reference
Red Hat, Inc. https://www.suse.com/security/cve/CVE-2024-6409.html
CVE Modified by Red Hat, Inc.8/22/2024 9:15:05 AM
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Reference
Red Hat, Inc. https://access.redhat.com/errata/RHSA-2024:5444 [No types assigned]
CVE Modified by Red Hat, Inc.8/07/2024 1:15:51 PM
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Reference
Red Hat, Inc. https://access.redhat.com/errata/RHSA-2024:4960 [No types assigned]
CVE Modified by Red Hat, Inc.8/07/2024 1:16:10 AM
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Red Hat, Inc. https://access.redhat.com/errata/RHSA-2024:4955 [No types assigned]
CVE Modified by Red Hat, Inc.8/02/2024 1:16:40 PM
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Reference
Red Hat, Inc. https://access.redhat.com/errata/RHSA-2024:4910 [No types assigned]
CVE Modified by Red Hat, Inc.7/24/2024 5:15:12 PM
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Reference
Red Hat, Inc. https://access.redhat.com/errata/RHSA-2024:4613 [No types assigned]
CVE Modified by Red Hat, Inc.7/23/2024 11:15:06 AM
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Reference
Red Hat, Inc. https://access.redhat.com/errata/RHSA-2024:4716 [No types assigned]
CVE Modified by Red Hat, Inc.7/13/2024 12:15:14 AM
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Description
A signal handler race condition vulnerability was found in OpenSSH's server (sshd) in Red Hat Enterprise Linux 9, where a client does not authenticate within LoginGraceTime seconds (120 by default, 600 in old OpenSSH versions), then sshd's SIGALRM handler is called asynchronously. However, this signal handler calls various functions that are not async-signal-safe, for example, syslog(). This issue leaves it vulnerable to a signal handler race condition on the cleanup_exit() function, which introduces the same vulnerability as CVE-2024-6387 in the unprivileged child of the SSHD server. As a consequence of a successful attack, in the worst case scenario, the attacker may be able to perform a remote code execution (RCE) within unprivileged user running the sshd server. This vulnerability affects only the sshd server shipped with Red Hat Enterprise Linux 9, while upstream versions of sshd are not impact by this flaw.
A race condition vulnerability was discovered in how signals are handled by OpenSSH's server (sshd). If a remote attacker does not authenticate within a set time period, then sshd's SIGALRM handler is called asynchronously. However, this signal handler calls various functions that are not async-signal-safe, for example, syslog(). As a consequence of a successful attack, in the worst case scenario, an attacker may be able to perform a remote code execution (RCE) as an unprivileged user running the sshd server.
Added
Reference
Red Hat, Inc. https://access.redhat.com/errata/RHSA-2024:4457 [No types assigned]
CVE Modified by Red Hat, Inc.7/12/2024 10:15:16 AM
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Old Value
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Reference
Red Hat, Inc. https://security.netapp.com/advisory/ntap-20240712-0003/ [No types assigned]
CVE Modified by Red Hat, Inc.7/10/2024 4:15:04 PM
Action
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Old Value
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Reference
Red Hat, Inc. https://github.com/openela-main/openssh/commit/c00da7741d42029e49047dd89e266d91dcfbffa0 [No types assigned]
CVE Modified by Red Hat, Inc.7/10/2024 1:15:12 PM
Action
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Old Value
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Reference
Red Hat, Inc. http://www.openwall.com/lists/oss-security/2024/07/10/2 [No types assigned]
CVE Modified by Red Hat, Inc.7/10/2024 12:15:04 PM
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Reference
Red Hat, Inc. http://www.openwall.com/lists/oss-security/2024/07/10/1 [No types assigned]
CVE Modified by Red Hat, Inc.7/10/2024 9:15:10 AM
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Reference
Red Hat, Inc. https://almalinux.org/blog/2024-07-09-cve-2024-6409/ [No types assigned]
Added
Reference
Red Hat, Inc. https://bugzilla.suse.com/show_bug.cgi?id=1227217 [No types assigned]
Added
Reference
Red Hat, Inc. https://www.suse.com/security/cve/CVE-2024-6409.html [No types assigned]
CVE Modified by Red Hat, Inc.7/09/2024 9:15:10 PM
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Reference
Red Hat, Inc. http://www.openwall.com/lists/oss-security/2024/07/09/5 [No types assigned]
CVE Modified by Red Hat, Inc.7/09/2024 11:15:12 AM
Action
Type
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Description
A signal handler race condition vulnerability was found in OpenSSH's server (sshd), where a client does not authenticate within LoginGraceTime seconds (120 by default, 600 in old OpenSSH versions), then sshd's SIGALRM handler is called asynchronously. However, this signal handler calls various functions that are not async-signal-safe, for example, syslog(). This issue leaves it vulnerable to a signal handler race condition on the cleanup_exit() function, which introduces the same vulnerability as CVE-2024-6387 in the unprivileged child of the SSHD server.
A signal handler race condition vulnerability was found in OpenSSH's server (sshd) in Red Hat Enterprise Linux 9, where a client does not authenticate within LoginGraceTime seconds (120 by default, 600 in old OpenSSH versions), then sshd's SIGALRM handler is called asynchronously. However, this signal handler calls various functions that are not async-signal-safe, for example, syslog(). This issue leaves it vulnerable to a signal handler race condition on the cleanup_exit() function, which introduces the same vulnerability as CVE-2024-6387 in the unprivileged child of the SSHD server. As a consequence of a successful attack, in the worst case scenario, the attacker may be able to perform a remote code execution (RCE) within unprivileged user running the sshd server. This vulnerability affects only the sshd server shipped with Red Hat Enterprise Linux 9, while upstream versions of sshd are not impact by this flaw.
CVE Modified by Red Hat, Inc.7/09/2024 8:15:21 AM
Action
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Reference
Red Hat, Inc. http://www.openwall.com/lists/oss-security/2024/07/09/2 [No types assigned]
CVE Modified by Red Hat, Inc.7/09/2024 2:15:03 AM
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Reference
Red Hat, Inc. https://explore.alas.aws.amazon.com/CVE-2024-6409.html [No types assigned]
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Red Hat, Inc. https://security-tracker.debian.org/tracker/CVE-2024-6409 [No types assigned]
Added
Reference
Red Hat, Inc. https://sig-security.rocky.page/issues/CVE-2024-6409/ [No types assigned]
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Reference
Red Hat, Inc. https://ubuntu.com/security/CVE-2024-6409 [No types assigned]
New CVE Received from Red Hat, Inc.7/08/2024 2:15:09 PM
Action
Type
Old Value
New Value
Added
Description
A signal handler race condition vulnerability was found in OpenSSH's server (sshd), where a client does not authenticate within LoginGraceTime seconds (120 by default, 600 in old OpenSSH versions), then sshd's SIGALRM handler is called asynchronously. However, this signal handler calls various functions that are not async-signal-safe, for example, syslog(). This issue leaves it vulnerable to a signal handler race condition on the cleanup_exit() function, which introduces the same vulnerability as CVE-2024-6387 in the unprivileged child of the SSHD server.
Added
CVSS V3.1
Red Hat, Inc. AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H
Added
CWE
Red Hat, Inc. CWE-364
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Reference
Red Hat, Inc. http://www.openwall.com/lists/oss-security/2024/07/08/2 [No types assigned]
Added
Reference
Red Hat, Inc. https://access.redhat.com/security/cve/CVE-2024-6409 [No types assigned]
Added
Reference
Red Hat, Inc. https://bugzilla.redhat.com/show_bug.cgi?id=2295085 [No types assigned]
Quick Info
CVE Dictionary Entry: CVE-2024-6409 NVD
Published Date: 07/08/2024 NVD
Last Modified: 11/21/2024
Source: Red Hat, Inc.
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