{"id":"CVE-2023-41991","published":"2023-09-21T19:15:11Z","modified":"2026-06-17T06:23:13Z","title":"Apple Multiple Products Improper Certificate Validation Vulnerability","vendor":"Apple","product":"Multiple Products","tier":"core","eol":null,"description":{"text":"A certificate validation issue was addressed. This issue is fixed in macOS Ventura 13.6, iOS 16.7 and iPadOS 16.7. A malicious app may be able to bypass signature validation. Apple is aware of a report that this issue may have been actively exploited against versions of iOS before iOS 16.7.","provenance":"source","from":"NVD"},"summary":{"text":"Apple Multiple Products (including macOS, iOS and iPadOS) contains an improper certificate validation flaw in its certificate validation handling. An attacker who can get a malicious app onto the device, with a user interaction required to run it, can bypass signature validation.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-23T07:14:15Z"},"cvss":{"score":5.5,"severity":"MEDIUM","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N","provenance":"source","from":"NVD"},"epss":{"score":0.1338,"percentile":0.9641,"date":"2026-10-29","provenance":"source"},"kev":{"dateAdded":"2023-09-25","dueDate":"2023-10-16","ransomware":false,"requiredAction":"Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.","notes":"https://support.apple.com/en-us/HT213926, https://support.apple.com/en-us/HT213927, https://support.apple.com/en-us/HT213928, https://support.apple.com/en-us/HT213929, https://support.apple.com/en-us/HT213931 ;  https://nvd.nist.gov/vuln/detail/CVE-2023-41991","provenance":"source"},"vulncheckKev":{"dateAdded":"2023-09-12","exploitedFirstSeen":"2023-09-12","ransomware":false,"evidence":[{"url":"https://docs.google.com/spreadsheets/d/1lkNJ0uQwbeC1ZTRrxdtuPLCIl7mlUreoKfSIgajnSyY/edit","date":"2023-09-12"},{"url":"https://support.apple.com/kb/HT213926","date":"2023-09-21"},{"url":"https://support.apple.com/kb/HT213927","date":"2023-09-21"},{"url":"https://support.apple.com/kb/HT213928","date":"2023-09-21"},{"url":"https://support.apple.com/kb/HT213929","date":"2023-09-21"},{"url":"https://support.apple.com/kb/HT213931","date":"2023-09-21"},{"url":"https://blog.google/threat-analysis-group/0-days-exploited-by-commercial-surveillance-vendor-in-egypt/","date":"2023-09-22"},{"url":"https://citizenlab.ca/2023/09/predator-in-the-wires-ahmed-eltantawy-targeted-with-predator-spyware-after-announcing-presidential-ambitions/","date":"2023-09-22"},{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2023-09-25"},{"url":"https://ti.qianxin.com/uploads/2024/02/02/dcc93e586f9028c68e7ab34c3326ff31.pdf","date":"2024-02-02"}],"evidenceTotal":16,"provenance":"source"},"exploited":true,"otx":{"pulseCount":50,"pulses":[{"name":"Actively_Exploited_Kev | Oct 30, 2026","url":"https://otx.alienvault.com/pulse/6ae35d889ea92b4ce19c2680","created":"2026-10-29"},{"name":"Actively_Exploited_Kev | Oct 29, 2026","url":"https://otx.alienvault.com/pulse/6ae20c1db17e7057ae7d9ad1","created":"2026-10-28"},{"name":"Actively_Exploited_Kev | Oct 28, 2026","url":"https://otx.alienvault.com/pulse/6ae0ba7e0e2a97ff7b218819","created":"2026-10-27"},{"name":"Actively_Exploited_Kev | Oct 27, 2026","url":"https://otx.alienvault.com/pulse/6adf68b85c3e852f3c111d18","created":"2026-10-26"},{"name":"Actively_Exploited_Kev | Oct 24, 2026","url":"https://otx.alienvault.com/pulse/6adb740e397c3ad4799aa4cd","created":"2026-10-23"},{"name":"Actively_Exploited_Kev | Oct 23, 2026","url":"https://otx.alienvault.com/pulse/6ada236fcfba2dfa730ea482","created":"2026-10-22"},{"name":"Actively_Exploited_Kev | Oct 22, 2026","url":"https://otx.alienvault.com/pulse/6ad8d33a077cbb5cab524d80","created":"2026-10-21"},{"name":"Actively_Exploited_Kev | Oct 21, 2026","url":"https://otx.alienvault.com/pulse/6ad78130c4d1ac2be83a8b6d","created":"2026-10-20"},{"name":"Actively_Exploited_Kev | Oct 20, 2026","url":"https://otx.alienvault.com/pulse/6ad62f63c24a405a3423cc13","created":"2026-10-19"},{"name":"Actively_Exploited_Kev | Oct 19, 2026","url":"https://otx.alienvault.com/pulse/6ad4dda174e5797d0bd238b7","created":"2026-10-18"}],"provenance":"machine"},"cwes":[{"id":"CWE-295","name":"Improper Certificate Validation"}],"references":[{"url":"https://support.apple.com/en-us/HT213927","tags":["Vendor Advisory"]},{"url":"https://support.apple.com/en-us/HT213931","tags":["Vendor Advisory"]},{"url":"https://support.apple.com/en-us/HT213927","tags":["Vendor Advisory"]},{"url":"https://support.apple.com/en-us/HT213931","tags":["Vendor Advisory"]},{"url":"https://support.apple.com/kb/HT213927","tags":["Vendor Advisory"]},{"url":"https://support.apple.com/kb/HT213931","tags":["Vendor Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-41991","tags":["US Government Resource"]}],"techniques":[{"id":"T1204.002","name":"Malicious File","tactics":["execution"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: User runs malicious app to trigger bypass","mappingType":"exploitation_technique","evidence":[{"from":"description","quote":"A malicious app may be able to bypass signature validation","start":115,"end":173}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"},{"id":"T1553.002","name":"Code Signing","tactics":["defense-impairment"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: Signature validation bypass enables code-signing evasion","mappingType":"primary_impact","evidence":[{"from":"description","quote":"A malicious app may be able to bypass signature validation","start":115,"end":173}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"}],"reports":[],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2023-46450","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2023-46450","exploited":true,"exploitedSince":"2023-09-25","provenance":"source"},"exploits":[],"exploitSources":{"pocGithub":{"count":3,"skipped":0,"earliest":"2023-11-28","earliestUrl":"https://github.com/itsgiddd/CVE-2023-41991","repos":[{"name":"itsgiddd/CVE-2023-41991","url":"https://github.com/itsgiddd/CVE-2023-41991","stars":6,"created":"2023-11-28"},{"name":"dmytrozykov/appsign","url":"https://github.com/dmytrozykov/appsign","stars":1,"created":"2025-03-18"},{"name":"lambertse/CoreTrust-bypass","url":"https://github.com/lambertse/CoreTrust-bypass","stars":0,"created":"2026-10-15"}]},"first":{"date":"2023-11-28","source":"PoC-in-GitHub","url":"https://github.com/itsgiddd/CVE-2023-41991"},"provenance":"source"},"exploitRefs":[],"flow":[{"stage":"exploitation","techniques":["T1204.002"],"provenance":"ai"},{"stage":"primary","techniques":["T1553.002"],"provenance":"ai"}],"timeline":[{"date":"2023-09-12","kind":"exploited-reported","label":"Exploitation 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KEV"},{"name":"Recent KEV listing","points":0.0,"detail":"added 1144 days ago"},{"name":"Known ransomware use","points":0.0,"detail":"not known"},{"name":"EPSS percentile","points":19.28,"detail":"percentile 0.9641"},{"name":"Named in threat reports","points":0.0,"detail":"0 reports"},{"name":"Public exploit code","points":5.0,"detail":"3 PoC-in-GitHub repos"},{"name":"Mentioned in OTX pulses","points":3.0,"detail":"50 pulses"},{"name":"CVSS severity","points":3.85,"detail":"base score 5.5"},{"name":"End-of-life product","points":0.0,"detail":"supported or unknown"}]},"lineage":{"familyId":"fam-class-apple-ios-macos-cwe-295"}}