{"id":"UBUNTU-CVE-2021-3595","details":"An invalid pointer initialization issue was found in the SLiRP networking implementation of QEMU. The flaw exists in the tftp_input() function and could occur while processing a udp packet that is smaller than the size of the 'tftp_t' structure. This issue may lead to out-of-bounds read access or indirect host memory disclosure to the guest. The highest threat from this vulnerability is to data confidentiality. This flaw affects libslirp versions prior to 4.6.0.","modified":"2026-04-22T14:50:35.043906Z","published":"2021-06-15T21:15:00Z","related":["USN-5009-1","USN-5009-2","USN-5010-1"],"upstream":["CVE-2021-3595"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2021-3595"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-5009-1"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-5010-1"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-5009-2"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2021-3595"}],"affected":[{"package":{"name":"qemu","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/qemu@1:2.11+dfsg-1ubuntu7.37?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1:2.11+dfsg-1ubuntu7.37"}]}],"versions":["1:2.10+dfsg-0ubuntu3","1:2.10+dfsg-0ubuntu4","1:2.10+dfsg-0ubuntu5","1:2.11+dfsg-1ubuntu1","1:2.11+dfsg-1ubuntu2","1:2.11+dfsg-1ubuntu4","1:2.11+dfsg-1ubuntu5","1:2.11+dfsg-1ubuntu6","1:2.11+dfsg-1ubuntu7","1:2.11+dfsg-1ubuntu7.1","1:2.11+dfsg-1ubuntu7.2","1:2.11+dfsg-1ubuntu7.3","1:2.11+dfsg-1ubuntu7.4","1:2.11+dfsg-1ubuntu7.5","1:2.11+dfsg-1ubuntu7.6","1:2.11+dfsg-1ubuntu7.7","1:2.11+dfsg-1ubuntu7.8","1:2.11+dfsg-1ubuntu7.9","1:2.11+dfsg-1ubuntu7.10","1:2.11+dfsg-1ubuntu7.12","1:2.11+dfsg-1ubuntu7.13","1:2.11+dfsg-1ubuntu7.14","1:2.11+dfsg-1ubuntu7.15","1:2.11+dfsg-1ubuntu7.17","1:2.11+dfsg-1ubuntu7.18","1:2.11+dfsg-1ubuntu7.19","1:2.11+dfsg-1ubuntu7.20","1:2.11+dfsg-1ubuntu7.21","1:2.11+dfsg-1ubuntu7.22","1:2.11+dfsg-1ubuntu7.23","1:2.11+dfsg-1ubuntu7.25","1:2.11+dfsg-1ubuntu7.26","1:2.11+dfsg-1ubuntu7.27","1:2.11+dfsg-1ubuntu7.28","1:2.11+dfsg-1ubuntu7.29","1:2.11+dfsg-1ubuntu7.31","1:2.11+dfsg-1ubuntu7.32","1:2.11+dfsg-1ubuntu7.33","1:2.11+dfsg-1ubuntu7.34","1:2.11+dfsg-1ubuntu7.35","1:2.11+dfsg-1ubuntu7.36"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"qemu","binary_version":"1:2.11+dfsg-1ubuntu7.37"},{"binary_version":"1:2.11+dfsg-1ubuntu7.37","binary_name":"qemu-block-extra"},{"binary_name":"qemu-guest-agent","binary_version":"1:2.11+dfsg-1ubuntu7.37"},{"binary_version":"1:2.11+dfsg-1ubuntu7.37","binary_name":"qemu-kvm"},{"binary_name":"qemu-system","binary_version":"1:2.11+dfsg-1ubuntu7.37"},{"binary_name":"qemu-system-arm","binary_version":"1:2.11+dfsg-1ubuntu7.37"},{"binary_name":"qemu-system-common","binary_version":"1:2.11+dfsg-1ubuntu7.37"},{"binary_name":"qemu-system-mips","binary_version":"1:2.11+dfsg-1ubuntu7.37"},{"binary_name":"qemu-system-misc","binary_version":"1:2.11+dfsg-1ubuntu7.37"},{"binary_name":"qemu-system-ppc","binary_version":"1:2.11+dfsg-1ubuntu7.37"},{"binary_name":"qemu-system-s390x","binary_version":"1:2.11+dfsg-1ubuntu7.37"},{"binary_name":"qemu-system-sparc","binary_version":"1:2.11+dfsg-1ubuntu7.37"},{"binary_version":"1:2.11+dfsg-1ubuntu7.37","binary_name":"qemu-system-x86"},{"binary_version":"1:2.11+dfsg-1ubuntu7.37","binary_name":"qemu-user"},{"binary_name":"qemu-user-binfmt","binary_version":"1:2.11+dfsg-1ubuntu7.37"},{"binary_name":"qemu-user-static","binary_version":"1:2.11+dfsg-1ubuntu7.37"},{"binary_name":"qemu-utils","binary_version":"1:2.11+dfsg-1ubuntu7.37"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-3595.json"}},{"package":{"name":"libslirp","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/libslirp@4.1.0-2ubuntu2.2?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.1.0-2ubuntu2.2"}]}],"versions":["4.0.0-1","4.0.0-2","4.1.0-1","4.1.0-2","4.1.0-2ubuntu1","4.1.0-2ubuntu2","4.1.0-2ubuntu2.1"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"libslirp0","binary_version":"4.1.0-2ubuntu2.2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-3595.json"}},{"package":{"name":"libslirp","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/libslirp@4.6.1-1?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.6.1-1"}]}],"versions":["4.4.0-1build1"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"libslirp0","binary_version":"4.6.1-1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2021/UBUNTU-CVE-2021-3595.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N"},{"type":"Ubuntu","score":"low"}]}