SUSE Amazon-SSM-Agent Important DoS Issues Fix Advisory 2026-4372

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## This update for amazon-ssm-agent fixes the following issue: * CVE-2026-56854: golang.org/x/crypto/ssh: source-address restriction bypassed in 5 callback families (bsc#1278681) * CVE-2026-56855: golang.org/x/crypto/ssh: prevent DoS on deadlocked established channel (bsc#1278681) * CVE-2026-78662: golang.org/x/crypto/ssh: prevent DoS on deadlocked undecided channel (bsc#1278681). Changes for amazon-ssm-agent: * Update to version 3.3.5390.0 ## Patch Instructions: To install this SUSE update use the SUSE recommended installation methods like YaST online_update or "zypper patch". Alternatively you can run the command listed for your product: * Public Cloud Module 15-SP4 zypper in -t patch SUSE-SLE-Module-Public-Cloud-15-SP4-2026-4372 * Public Cloud Module 15-SP5

## This update for amazon-ssm-agent fixes the following issue: * CVE-2026-56854: golang.org/x/crypto/ssh: source-address restriction bypassed in 5 callback families (bsc#1278681) * CVE-2026-56855: golang.org/x/crypto/ssh: prevent DoS on deadlocked established channel (bsc#1278681) * CVE-2026-78662: golang.org/x/crypto/ssh: prevent DoS on deadlocked undecided channel (bsc#1278681). Changes for amazon-ssm-agent: * Update to version 3.3.5390.0 ## Patch Instructions: To install this SUSE update use the SUSE recommended installation methods like YaST online_update or "zypper patch". Alternatively you can run the command listed for your product: * Public Cloud Module 15-SP4 zypper in -t patch SUSE-SLE-Module-Public-Cloud-15-SP4-2026-4372 * Public Cloud Module 15-SP5

* CVE-2026-56854 ( SUSE ): 8.6

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

* CVE-2026-56854 ( SUSE ): 8.1 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

* CVE-2026-56854 ( NVD ): 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

* CVE-2026-56855 ( SUSE ): 8.7

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

* CVE-2026-56855 ( SUSE ): 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

* CVE-2026-56855 ( NVD ): 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

* CVE-2026-78662 ( SUSE ): 8.7

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

* CVE-2026-78662 ( SUSE ): 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Announcement ID: SUSE-SU-2026:4372-1 Release Date: 2026-09-28T15:11:22Z Rating: important

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