{"id":"UBUNTU-CVE-2026-43620","details":"Rsync version 3.4.2 and prior contain a receiver-side out-of-bounds array read vulnerability in recv_files() in receiver.c that allows a malicious rsync server to crash the rsync client process. Attackers can exploit the vulnerability by setting CF_INC_RECURSE in compatibility flags and sending a specially crafted file list where the first sorted entry is not the leading dot directory, followed by a transfer record with ndx=0 and an iflag word without ITEM_TRANSFER, causing the receiver to read 8 bytes before the allocated pointer array and dereference an invalid pointer at an unmapped address, resulting in a deterministic SIGSEGV crash of the rsync client.","modified":"2026-06-16T13:44:20.967323121Z","published":"2026-05-20T00:00:00Z","related":["USN-8283-1","USN-8349-1","USN-8349-2","USN-8349-3"],"upstream":["CVE-2026-43620"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-43620"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-43620"},{"type":"REPORT","url":"https://github.com/RsyncProject/rsync/security/advisories/GHSA-28pw-r563-rxvm"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8283-1"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8349-1"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8349-2"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8349-3"}],"affected":[{"package":{"name":"rsync","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/rsync?arch=source&distro=esm-infra-legacy%2Ftrusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.1.0-2ubuntu0.4+esm3"}]}],"versions":["3.0.9-4ubuntu1","3.1.0-2","3.1.0-2ubuntu0.1","3.1.0-2ubuntu0.2","3.1.0-2ubuntu0.3","3.1.0-2ubuntu0.4","3.1.0-2ubuntu0.4+esm1","3.1.0-2ubuntu0.4+esm2"],"ecosystem_specific":{"binaries":[{"binary_name":"rsync","binary_version":"3.1.0-2ubuntu0.4+esm3"}],"availability":"Available with Ubuntu Pro with Legacy support add-on: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43620.json"}},{"package":{"name":"rsync","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/rsync?arch=source&distro=esm-infra-legacy%2Fxenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.1.1-3ubuntu1.3+esm5"}]}],"versions":["3.1.1-3","3.1.1-3ubuntu1","3.1.1-3ubuntu1.1","3.1.1-3ubuntu1.2","3.1.1-3ubuntu1.3","3.1.1-3ubuntu1.3+esm1","3.1.1-3ubuntu1.3+esm2","3.1.1-3ubuntu1.3+esm3","3.1.1-3ubuntu1.3+esm4"],"ecosystem_specific":{"binaries":[{"binary_name":"rsync","binary_version":"3.1.1-3ubuntu1.3+esm5"}],"availability":"Available with Ubuntu Pro with Legacy support add-on: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43620.json"}},{"package":{"name":"rsync","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/rsync?arch=source&distro=esm-infra%2Fbionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.1.2-2.1ubuntu1.6+esm3"}]}],"versions":["3.1.2-2","3.1.2-2.1","3.1.2-2.1ubuntu1","3.1.2-2.1ubuntu1.1","3.1.2-2.1ubuntu1.2","3.1.2-2.1ubuntu1.3","3.1.2-2.1ubuntu1.4","3.1.2-2.1ubuntu1.5","3.1.2-2.1ubuntu1.6","3.1.2-2.1ubuntu1.6+esm1","3.1.2-2.1ubuntu1.6+esm2"],"ecosystem_specific":{"binaries":[{"binary_name":"rsync","binary_version":"3.1.2-2.1ubuntu1.6+esm3"}],"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43620.json"}},{"package":{"name":"rsync","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/rsync?arch=source&distro=esm-infra%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.1.3-8ubuntu0.9+esm1"}]}],"versions":["3.1.3-6","3.1.3-8","3.1.3-8ubuntu0.1","3.1.3-8ubuntu0.2","3.1.3-8ubuntu0.3","3.1.3-8ubuntu0.4","3.1.3-8ubuntu0.5","3.1.3-8ubuntu0.7","3.1.3-8ubuntu0.8","3.1.3-8ubuntu0.9"],"ecosystem_specific":{"binaries":[{"binary_name":"rsync","binary_version":"3.1.3-8ubuntu0.9+esm1"}],"availability":"Available with Ubuntu Pro (Infra-only): https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43620.json"}},{"package":{"name":"rsync","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/rsync?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.2.7-0ubuntu0.22.04.6"}]}],"versions":["3.2.3-4ubuntu1","3.2.3-4ubuntu2","3.2.3-8ubuntu1","3.2.3-8ubuntu2","3.2.3-8ubuntu3","3.2.3-8ubuntu3.1","3.2.7-0ubuntu0.22.04.2","3.2.7-0ubuntu0.22.04.3","3.2.7-0ubuntu0.22.04.4"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"rsync","binary_version":"3.2.7-0ubuntu0.22.04.6"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43620.json"}},{"package":{"name":"rsync","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/rsync?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.2.7-1ubuntu1.4"}]}],"versions":["3.2.7-1","3.2.7-1build1","3.2.7-1build2","3.2.7-1ubuntu1","3.2.7-1ubuntu1.1","3.2.7-1ubuntu1.2"],"ecosystem_specific":{"binaries":[{"binary_name":"rsync","binary_version":"3.2.7-1ubuntu1.4"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43620.json"}},{"package":{"name":"rsync","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/rsync?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.4.1+ds1-5ubuntu1.2"}]}],"versions":["3.4.1+ds1-3","3.4.1+ds1-4","3.4.1+ds1-5","3.4.1+ds1-5ubuntu1"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"rsync","binary_version":"3.4.1+ds1-5ubuntu1.2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43620.json"}},{"package":{"name":"rsync","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/rsync?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.4.1+ds1-7ubuntu0.2"}]}],"versions":["3.4.1+ds1-5ubuntu1","3.4.1+ds1-6","3.4.1+ds1-7"],"ecosystem_specific":{"binaries":[{"binary_version":"3.4.1+ds1-7ubuntu0.2","binary_name":"rsync"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43620.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"},{"type":"Ubuntu","score":"medium"}]}