{"id":"UBUNTU-CVE-2026-122127","details":"CESNET ipfixcol2 2.7.1 before 2.9.0 contains a heap-based buffer overflow in Lz4Decoder.cpp that allows unauthenticated network peers to write past heap buffers. Attackers can declare a small ring buffer_size followed by a large decompressed_size to write up to 65535 controlled bytes and crash the collector.","modified":"2026-11-06T01:00:24.286717654Z","published":"2026-11-05T00:00:00Z","upstream":["CVE-2026-122127"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-122127"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-122127"},{"type":"REPORT","url":"https://github.com/CESNET/ipfixcol2"},{"type":"REPORT","url":"https://github.com/CESNET/ipfixcol2/blob/v2.8.0/src/plugins/input/tcp/src/Lz4Decoder.cpp#L139-L151"},{"type":"REPORT","url":"https://github.com/CESNET/ipfixcol2/commit/fd5cb168efb4b864d33f655174711b2779cef502"},{"type":"REPORT","url":"https://github.com/CESNET/ipfixcol2/releases/tag/v2.9.0"},{"type":"REPORT","url":"https://www.vulncheck.com/advisories/cesnet-ipfixcol2-2.7.1-before-2.9.0-heap-buffer-overflow-via-tcp-lz4-decoder"}],"affected":[{"package":{"name":"ipfixcol2","ecosystem":"Ubuntu:26.10","purl":"pkg:deb/ubuntu/ipfixcol2?arch=source&distro=stonking"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.8.0+20260519-1","2.8.0+20260519-2","2.8.0+20260701-1"],"ecosystem_specific":{"binaries":[{"binary_version":"2.8.0+20260701-1","binary_name":"ipfixcol2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-122127.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"CVSS_V4","score":"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"},{"type":"Ubuntu","score":"medium"}]}