{"id":"UBUNTU-CVE-2026-16599","details":"GNU wget is vulnerable to denial of service in its FTP OPIE/S-KEY authentication functionality. The server-supplied sequence number from the FTP challenge line is used as an iteration count for an MD5 key-derivation loop without any upper bound validation. A malicious FTP server or a network attacker positioned to intercept FTP traffic can send a crafted OPIE challenge with a sequence number near INT_MAX, causing wget to perform up to approximately 2.1 billion MD5 computations and suspend for some time. The --timeout option does not mitigate this because it applies only to network I/O, not CPU computation. This issue was fixed in commit e9697d98e7249b0f68a6be040a4f3dcc5bc101fa","modified":"2026-09-02T19:39:46.030565611Z","published":"2026-08-25T15:16:00Z","upstream":["CVE-2026-16599"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-16599"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-16599"},{"type":"REPORT","url":"https://cert.pl/en/posts/2026/08/CVE-2026-16599/"}],"affected":[{"package":{"name":"wget","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/wget?arch=source&distro=esm-infra-legacy%2Ftrusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.14-2ubuntu1","1.14-5ubuntu1","1.15-1ubuntu1","1.15-1ubuntu1.14.04.1","1.15-1ubuntu1.14.04.2","1.15-1ubuntu1.14.04.3","1.15-1ubuntu1.14.04.4","1.15-1ubuntu1.14.04.5","1.15-1ubuntu1.14.04.5+esm2","1.15-1ubuntu1.14.04.5+esm3","1.15-1ubuntu1.14.04.5+esm4"],"ecosystem_specific":{"binaries":[{"binary_version":"1.15-1ubuntu1.14.04.5+esm4","binary_name":"wget"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-16599.json"}},{"package":{"name":"wget","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/wget?arch=source&distro=esm-infra-legacy%2Fxenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.16.1-1ubuntu1","1.17.1-1ubuntu1","1.17.1-1ubuntu1.1","1.17.1-1ubuntu1.2","1.17.1-1ubuntu1.3","1.17.1-1ubuntu1.4","1.17.1-1ubuntu1.5","1.17.1-1ubuntu1.5+esm1","1.17.1-1ubuntu1.5+esm3","1.17.1-1ubuntu1.5+esm4","1.17.1-1ubuntu1.5+esm5"],"ecosystem_specific":{"binaries":[{"binary_name":"wget","binary_version":"1.17.1-1ubuntu1.5+esm5"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-16599.json"}},{"package":{"name":"wget","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/wget?arch=source&distro=esm-infra%2Fbionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.19.1-3ubuntu1","1.19.1-3ubuntu1.1","1.19.2-1ubuntu1","1.19.3-2ubuntu1","1.19.4-1ubuntu2","1.19.4-1ubuntu2.1","1.19.4-1ubuntu2.2","1.19.4-1ubuntu2.2+esm1","1.19.4-1ubuntu2.2+esm3","1.19.4-1ubuntu2.2+esm4","1.19.4-1ubuntu2.2+esm5"],"ecosystem_specific":{"binaries":[{"binary_version":"1.19.4-1ubuntu2.2+esm5","binary_name":"wget"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-16599.json"}},{"package":{"name":"wget","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/wget?arch=source&distro=esm-infra%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.20.3-1ubuntu1","1.20.3-1ubuntu2","1.20.3-1ubuntu2.1","1.20.3-1ubuntu2.1+esm2","1.20.3-1ubuntu2.1+esm3","1.20.3-1ubuntu2.1+esm4"],"ecosystem_specific":{"binaries":[{"binary_version":"1.20.3-1ubuntu2.1+esm4","binary_name":"wget"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-16599.json"}},{"package":{"name":"wget","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/wget?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.21-1ubuntu3","1.21-1ubuntu4","1.21-1ubuntu5","1.21.2-2ubuntu1","1.21.2-2ubuntu1.1","1.21.2-2ubuntu1.3","1.21.2-2ubuntu1.4","1.21.2-2ubuntu1.5"],"ecosystem_specific":{"binaries":[{"binary_version":"1.21.2-2ubuntu1.5","binary_name":"wget"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-16599.json"}},{"package":{"name":"wget","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/wget?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.21.3-1ubuntu1","1.21.4-1ubuntu1","1.21.4-1ubuntu2","1.21.4-1ubuntu3","1.21.4-1ubuntu4","1.21.4-1ubuntu4.1","1.21.4-1ubuntu4.3","1.21.4-1ubuntu4.4","1.21.4-1ubuntu4.5"],"ecosystem_specific":{"binaries":[{"binary_name":"wget","binary_version":"1.21.4-1ubuntu4.5"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-16599.json"}},{"package":{"name":"wget","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/wget?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.25.0-2ubuntu3","1.25.0-2ubuntu4","1.25.0-2ubuntu4.2","1.25.0-2ubuntu4.3","1.25.0-2ubuntu4.4"],"ecosystem_specific":{"binaries":[{"binary_name":"wget","binary_version":"1.25.0-2ubuntu4.4"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-16599.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N"},{"type":"Ubuntu","score":"medium"}]}