{"id":"CVE-2026-79604","aliases":["DEBIAN-CVE-2026-79604","UBUNTU-CVE-2026-79604"],"status":"published","description":"oxenstored: Unbounded accumulation of watches: Oxenstored maintains two datastructures about watches; one global trie, and one hashtable tracked per domain.  When a xenbus reconnect is requested, watches are not cleared out of the global trie. A guest can cause unbounded memory usage in oxenstored.  This can lead to a system-wide DoS. All version of Xen from 4.6 onwards are vulnerable. Only systems using the Ocaml Xenstored implementation are vulnerable. Systems using the C Xenstored implementation are not vulnerable.","facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"published":"2026-09-08T12:00:00Z","modified":"2026-11-04T23:02:29Z","fixes":[{"ecosystem":"Debian:12","package":"xen","fixed_in":["4.17.7+13-g2445b30a44-0+deb12u1"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"xen","fixed_in":["4.20.4+39-gf1e1321c87-0+deb13u1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"xen","fixed_in":["4.20.4+39-gf1e1321c87-1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Debian:12","package":"xen","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.17.7+13-g2445b30a44-0+deb12u1"}]}],"versions":["4.17.1+2-gb773c48e36-1","4.17.2+55-g0b56bed864-1","4.17.2+76-ge1f9cb16e2-1","4.17.2+76-ge1f9cb16e2-1~deb12u1","4.17.2-1","4.17.3+10-g091466ba55-1","4.17.3+10-g091466ba55-1.1","4.17.3+10-g091466ba55-1.1~exp1","4.17.3+10-g091466ba55-1.1~exp2","4.17.3+10-g091466ba55-1~deb12u1","4.17.3+36-g54dacb5c02-1","4.17.5+23-ga4e5191dc0-1","4.17.5+23-ga4e5191dc0-1+deb12u1","4.17.5+72-g01140da4e8-1","4.17.7-0+deb12u1"]},{"source":"osv","ecosystem":"Debian:13","package":"xen","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.20.4+39-gf1e1321c87-0+deb13u1"}]}],"versions":["4.20.0+68-g35cb38b222-1","4.20.2+37-g61ff35323e-0+deb13u1","4.20.2+37-g61ff35323e-1","4.20.2+7-g1badcf5035-0+deb13u1","4.20.2+7-g1badcf5035-1","4.20.2+7-g1badcf5035-2","4.20.3+127-gc42374a105-0+deb13u1","4.20.3+127-gc42374a105-1"]},{"source":"osv","ecosystem":"Debian:14","package":"xen","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"4.20.4+39-gf1e1321c87-1"}]}],"versions":["4.20.0+68-g35cb38b222-1","4.20.2+37-g61ff35323e-1","4.20.2+7-g1badcf5035-1","4.20.2+7-g1badcf5035-2","4.20.3+127-gc42374a105-1"]},{"source":"osv","ecosystem":"Ubuntu:16.04:LTS","package":"xen","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.5.1-0ubuntu1","4.5.1-0ubuntu2","4.6.0-1ubuntu1","4.6.0-1ubuntu2","4.6.0-1ubuntu4","4.6.0-1ubuntu4.1","4.6.0-1ubuntu4.2","4.6.0-1ubuntu4.3","4.6.5-0ubuntu1","4.6.5-0ubuntu1.1","4.6.5-0ubuntu1.2","4.6.5-0ubuntu1.4"]},{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"xen","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.9.0-0ubuntu3","4.9.0-0ubuntu4","4.9.2-0ubuntu1"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"xen","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.9.2-0ubuntu2","4.9.2-0ubuntu6","4.9.2-0ubuntu7","4.11.3+24-g14b62ab3e5-1ubuntu1","4.11.3+24-g14b62ab3e5-1ubuntu2","4.11.3+24-g14b62ab3e5-1ubuntu2.2","4.11.3+24-g14b62ab3e5-1ubuntu2.3"]},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"xen","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.11.4+24-gddaaccbbab-1ubuntu2","4.16.0-1~ubuntu2","4.16.0-1~ubuntu2.1"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"xen","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.17.2-1","4.17.2+55-g0b56bed864-1","4.17.2+76-ge1f9cb16e2-1","4.17.2+76-ge1f9cb16e2-1ubuntu1","4.17.3+10-g091466ba55-1","4.17.3+10-g091466ba55-1.1ubuntu2","4.17.3+10-g091466ba55-1.1ubuntu3"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"xen","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.20.2+7-g1badcf5035-2build2","4.20.2+37-g61ff35323e-1ubuntu1","4.20.3+127-gc42374a105-1"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"xen","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.20.0+68-g35cb38b222-1","4.20.2+7-g1badcf5035-2","4.20.2+7-g1badcf5035-2build2"]}],"references":[{"url":"https://security-tracker.debian.org/tracker/CVE-2026-79604","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-79604","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-79604","tags":["report"]}],"sources":{"osv":[{"id":"DEBIAN-CVE-2026-79604","status":"published","published":"2026-09-08T20:47:33.500866434Z","modified":"2026-11-04T23:02:29.604479228Z","updated_at":"2026-11-04T23:09:59.08306Z"},{"id":"UBUNTU-CVE-2026-79604","description":"oxenstored: Unbounded accumulation of watches: Oxenstored maintains two datastructures about watches; one global trie, and one hashtable tracked per domain.  When a xenbus reconnect is requested, watches are not cleared out of the global trie. A guest can cause unbounded memory usage in oxenstored.  This can lead to a system-wide DoS. All version of Xen from 4.6 onwards are vulnerable. Only systems using the Ocaml Xenstored implementation are vulnerable. Systems using the C Xenstored implementation are not vulnerable.","status":"published","published":"2026-09-08T12:00:00Z","modified":"2026-10-17T13:01:09.904918846Z","updated_at":"2026-11-02T16:57:18.015985Z"}]}}