{"id":"CVE-2016-1839","url":"https://www.cyber-defence.io/tools/cve/CVE-2016-1839","generatedAt":"2026-10-27T17:43:01.702Z","title":"The xmlDictAddString function in libxml2 before 2.9.4, as used in Apple iOS before 9.3.2, OS X before 10.11.5, tvOS before 9.2.1, and watchOS before 2.2.1, allows remote attackers to cause a denial of service (heap-based buffer over-read) via a crafted…","description":"The xmlDictAddString function in libxml2 before 2.9.4, as used in Apple iOS before 9.3.2, OS X before 10.11.5, tvOS before 9.2.1, and watchOS before 2.2.1, allows remote attackers to cause a denial of service (heap-based buffer over-read) via a crafted XML document.","published":"2016-05-20T10:59:53.000Z","lastModified":"2026-06-17T00:42:44.000Z","status":"Modified","sourceIdentifier":"product-security@apple.com","cvss":{"version":"3.0","score":5.5,"severity":"MEDIUM","vector":"CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"},"cwe":["CWE-125"],"affected":["apple/iphone os","apple/mac os x","apple/tvos","apple/watchos","canonical/ubuntu linux","debian/debian linux","redhat/enterprise linux desktop","redhat/enterprise linux server","redhat/enterprise linux server aus","redhat/enterprise linux server eus","redhat/enterprise linux server tus","redhat/enterprise linux workstation","mcafee/web gateway","xmlsoft/libxml2"],"epss":{"score":0.07347,"percentile":0.94357,"date":"2026-10-26","history":[{"date":"2026-09-21","score":0.12826,"percentile":0.96166},{"date":"2026-09-22","score":0.07347,"percentile":0.94119}]},"kev":{"listed":false},"exploits":{"count":1,"verified":true,"firstPublished":"2016-02-24","source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[{"edbId":39491,"kind":"exploit","title":"libxml2 - xmlDictAddString Heap Buffer Overread","url":"https://www.exploit-db.com/exploits/39491","sourceUrl":"https://gitlab.com/exploit-database/exploitdb/-/blob/main/exploits/linux/dos/39491.txt","file":"exploits/linux/dos/39491.txt","published":"2016-02-24","added":"2016-02-24","updated":"2016-02-24","author":"Google Security Research","type":"dos","platform":"linux","port":null,"verified":true,"codes":["CVE-2016-1839"],"tags":null,"aliases":null,"applicationUrl":null,"screenshotUrl":null,"referenceUrl":"https://code.google.com/p/google-security-research/issues/detail?id=637"}]},"verdict":{"level":"high","text":"A public exploit is published in Exploit-DB (verified), so the technical barrier is gone even though the severity is medium and EPSS is 7.3%. Treat it as high on anything reachable from the internet."},"changes":[{"kind":"epss","label":"EPSS jump","at":"2026-09-21T00:00:00.000Z","detail":{"to":0.12826,"from":0.07347,"percentile":0.96166},"summary":"EPSS moved from 7.3% to 12.8% probability of exploitation in the next thirty days."}],"references":[{"url":"http://lists.apple.com/archives/security-announce/2016/May/msg00001.html","tags":["Mailing List","Vendor Advisory"],"source":"product-security@apple.com"},{"url":"http://lists.apple.com/archives/security-announce/2016/May/msg00002.html","tags":["Mailing List","Vendor Advisory"],"source":"product-security@apple.com"},{"url":"http://lists.apple.com/archives/security-announce/2016/May/msg00003.html","tags":["Mailing List","Vendor Advisory"],"source":"product-security@apple.com"},{"url":"http://lists.apple.com/archives/security-announce/2016/May/msg00004.html","tags":["Mailing List","Vendor Advisory"],"source":"product-security@apple.com"},{"url":"http://rhn.redhat.com/errata/RHSA-2016-2957.html","tags":["Third Party Advisory"],"source":"product-security@apple.com"},{"url":"http://www.oracle.com/technetwork/topics/security/bulletinjul2016-3090568.html","tags":["Third Party Advisory"],"source":"product-security@apple.com"},{"url":"http://www.oracle.com/technetwork/topics/security/linuxbulletinjul2016-3090544.html","tags":["Third Party Advisory"],"source":"product-security@apple.com"},{"url":"http://www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.html","tags":["Third Party Advisory"],"source":"product-security@apple.com"},{"url":"http://www.securityfocus.com/bid/90691","tags":["Third Party Advisory","VDB Entry"],"source":"product-security@apple.com"},{"url":"http://www.securitytracker.com/id/1035890","tags":["Third Party Advisory","VDB Entry"],"source":"product-security@apple.com"},{"url":"http://www.securitytracker.com/id/1038623","tags":["Third Party Advisory","VDB Entry"],"source":"product-security@apple.com"},{"url":"http://www.ubuntu.com/usn/USN-2994-1","tags":["Third Party Advisory"],"source":"product-security@apple.com"},{"url":"http://xmlsoft.org/news.html","tags":["Release Notes","Vendor Advisory"],"source":"product-security@apple.com"},{"url":"https://access.redhat.com/errata/RHSA-2016:1292","tags":["Third Party Advisory"],"source":"product-security@apple.com"},{"url":"https://bugzilla.gnome.org/show_bug.cgi?id=758605","tags":["Exploit","Issue Tracking","Third Party Advisory"],"source":"product-security@apple.com"},{"url":"https://git.gnome.org/browse/libxml2/commit/?id=a820dbeac29d330bae4be05d9ecd939ad6b4aa33","tags":["Patch","Third Party Advisory"],"source":"product-security@apple.com"},{"url":"https://kc.mcafee.com/corporate/index?page=content&id=SB10170","tags":["Patch","Third Party Advisory"],"source":"product-security@apple.com"},{"url":"https://security.gentoo.org/glsa/201701-37","tags":["Third Party Advisory"],"source":"product-security@apple.com"},{"url":"https://support.apple.com/HT206564","tags":["Vendor Advisory"],"source":"product-security@apple.com"},{"url":"https://support.apple.com/HT206566","tags":["Vendor Advisory"],"source":"product-security@apple.com"},{"url":"https://support.apple.com/HT206567","tags":["Vendor Advisory"],"source":"product-security@apple.com"},{"url":"https://support.apple.com/HT206568","tags":["Vendor Advisory"],"source":"product-security@apple.com"},{"url":"https://www.debian.org/security/2016/dsa-3593","tags":["Third Party Advisory"],"source":"product-security@apple.com"},{"url":"https://www.tenable.com/security/tns-2016-18","tags":["Third Party Advisory"],"source":"product-security@apple.com"},{"url":"http://lists.apple.com/archives/security-announce/2016/May/msg00001.html","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://lists.apple.com/archives/security-announce/2016/May/msg00002.html","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://lists.apple.com/archives/security-announce/2016/May/msg00003.html","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://lists.apple.com/archives/security-announce/2016/May/msg00004.html","tags":["Mailing List","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://rhn.redhat.com/errata/RHSA-2016-2957.html","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.oracle.com/technetwork/topics/security/bulletinjul2016-3090568.html","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.oracle.com/technetwork/topics/security/linuxbulletinjul2016-3090544.html","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.html","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.securityfocus.com/bid/90691","tags":["Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.securitytracker.com/id/1035890","tags":["Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.securitytracker.com/id/1038623","tags":["Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.ubuntu.com/usn/USN-2994-1","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://xmlsoft.org/news.html","tags":["Release Notes","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://access.redhat.com/errata/RHSA-2016:1292","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://bugzilla.gnome.org/show_bug.cgi?id=758605","tags":["Exploit","Issue Tracking","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://git.gnome.org/browse/libxml2/commit/?id=a820dbeac29d330bae4be05d9ecd939ad6b4aa33","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://kc.mcafee.com/corporate/index?page=content&id=SB10170","tags":["Patch","Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/201701-37","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://support.apple.com/HT206564","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://support.apple.com/HT206566","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://support.apple.com/HT206567","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://support.apple.com/HT206568","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.debian.org/security/2016/dsa-3593","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.tenable.com/security/tns-2016-18","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2016-1839","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}