{"id":"CVE-2020-28949","published":"2020-11-19T19:15:11Z","modified":"2026-06-17T03:10:53Z","title":"PEAR Archive_Tar Deserialization of Untrusted Data Vulnerability","vendor":"PEAR","product":"Archive_Tar","tier":"core","eol":null,"description":{"text":"Archive_Tar through 1.4.10 has :// filename sanitization only to address phar attacks, and thus any other stream-wrapper attack (such as file:// to overwrite files) can still succeed.","provenance":"source","from":"NVD"},"summary":{"text":"The PEAR Archive_Tar library, up to and including version 1.4.10, contains a deserialization flaw in how it handles untrusted archive filenames. Its sanitization of stream-wrapper prefixes (the \"://\" handling) only defends against phar attacks, leaving other wrappers such as file:// usable. An attacker who can get a user or process to open a crafted archive would need local access and user interaction, and could then overwrite files on the system.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-29T07:54:07Z"},"cvss":{"score":7.8,"severity":"HIGH","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","provenance":"source","from":"NVD"},"epss":{"score":0.84554,"percentile":0.99701,"date":"2026-10-29","provenance":"source"},"kev":{"dateAdded":"2022-08-25","dueDate":"2022-09-15","ransomware":false,"requiredAction":"Apply updates per vendor instructions.","notes":"https://pear.php.net/bugs/bug.php?id=27002, https://www.drupal.org/sa-core-2020-013, https://access.redhat.com/security/cve/cve-2020-28949; https://nvd.nist.gov/vuln/detail/CVE-2020-28949","provenance":"source"},"vulncheckKev":{"dateAdded":"2022-08-25","exploitedFirstSeen":"2022-08-25","ransomware":true,"evidence":[{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2022-08-25"},{"url":"https://info.securin.io/hubfs/Securin%20Ransomware%20Report%202023.pdf","date":"2023-02-14"},{"url":"https://www.trustwave.com/hubfs/Web/Library/Documents_pdf/2024_Trustwave_Public_Sector_Threat_Landscape.pdf","date":"2024-05-14"}],"evidenceTotal":3,"provenance":"source"},"exploited":true,"otx":{"pulseCount":50,"pulses":[{"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"},{"name":"Actively_Exploited_Kev | Oct 18, 2026","url":"https://otx.alienvault.com/pulse/6ad38c22e1848f8189d1c121","created":"2026-10-17"}],"provenance":"machine"},"cwes":[{"id":"CWE-74","name":"Improper Neutralization of Special Elements in Output Used by a Downstream Component"}],"references":[{"url":"http://packetstormsecurity.com/files/161095/PEAR-Archive_Tar-Arbitrary-File-Write.html","tags":["Exploit","Third Party Advisory","VDB Entry"]},{"url":"https://github.com/pear/Archive_Tar/issues/33","tags":["Exploit","Issue Tracking","Vendor Advisory"]},{"url":"https://lists.debian.org/debian-lts-announce/2020/11/msg00045.html","tags":["Mailing List","Third Party Advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/42GPGVVFTLJYAKRI75IVB5R45NYQGEUR/","tags":["Mailing List","Third Party Advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4V35LBRM6HBCXBVCITKQ4UEBTXO2EG7B/","tags":["Mailing List","Third Party Advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5KSFM672XW3X6BR7TVKRD63SLZGKK437/","tags":["Mailing List","Third Party Advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KWM4CTMEGAC4I2CHYNJVSROY4CVXVEUT/","tags":["Mailing List","Third Party Advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NBYZSHYTIOBK6V7C4N7TP6KIKCRKLVWP/","tags":["Mailing List","Third Party Advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VJQQYDAOWHD6RDITDRPHFW7WY6BS3V5N/","tags":["Mailing List","Third Party Advisory"]},{"url":"https://security.gentoo.org/glsa/202101-23","tags":["Third Party Advisory"]},{"url":"https://www.debian.org/security/2020/dsa-4817","tags":["Mailing List","Third Party Advisory"]},{"url":"https://www.drupal.org/sa-core-2020-013","tags":["Third Party Advisory"]},{"url":"http://packetstormsecurity.com/files/161095/PEAR-Archive_Tar-Arbitrary-File-Write.html","tags":["Exploit","Third Party Advisory","VDB Entry"]},{"url":"https://github.com/pear/Archive_Tar/issues/33","tags":["Exploit","Issue Tracking","Vendor Advisory"]},{"url":"https://lists.debian.org/debian-lts-announce/2020/11/msg00045.html","tags":["Mailing List","Third Party Advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/42GPGVVFTLJYAKRI75IVB5R45NYQGEUR/","tags":["Mailing List","Third Party Advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/4V35LBRM6HBCXBVCITKQ4UEBTXO2EG7B/","tags":["Mailing List","Third Party Advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/5KSFM672XW3X6BR7TVKRD63SLZGKK437/","tags":["Mailing List","Third Party Advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/KWM4CTMEGAC4I2CHYNJVSROY4CVXVEUT/","tags":["Mailing List","Third Party Advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NBYZSHYTIOBK6V7C4N7TP6KIKCRKLVWP/","tags":["Mailing List","Third Party Advisory"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VJQQYDAOWHD6RDITDRPHFW7WY6BS3V5N/","tags":["Mailing List","Third Party Advisory"]},{"url":"https://security.gentoo.org/glsa/202101-23","tags":["Third Party Advisory"]},{"url":"https://www.debian.org/security/2020/dsa-4817","tags":["Mailing List","Third Party Advisory"]},{"url":"https://www.drupal.org/sa-core-2020-013","tags":["Third Party Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-28949","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 opens malicious archive; requires user interaction","mappingType":"exploitation_technique","evidence":[{"from":"description","quote":"Archive_Tar through 1.4.10 has :// filename sanitization only","start":0,"end":61}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"},{"id":"T1005","name":"Data from Local System","tactics":["collection"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: file:// stream wrapper overwrites arbitrary local files","mappingType":"primary_impact","evidence":[{"from":"description","quote":"any other stream-wrapper attack (such as file:// to overwrite files)","start":96,"end":164}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"}],"reports":[],"affected":[{"ecosystem":"Packagist","package":"pear/archive_tar","vulnerableRanges":["<1.4.11"],"patched":["1.4.11"],"from":["GHSA-75c5-f4gw-38r9"],"provenance":"source"},{"ecosystem":"Packagist","package":"drupal/core","vulnerableRanges":[">=8.0.0, <8.8.12",">=8.9.0, <8.9.10",">=9.0.0, <9.0.9"],"patched":["8.8.12","8.9.10","9.0.9"],"from":["DRUPAL-CORE-2020-013"],"provenance":"source"}],"advisories":[{"id":"GHSA-75c5-f4gw-38r9","url":"https://github.com/advisories/GHSA-75c5-f4gw-38r9","severity":"HIGH","ecosystem":"Packagist","package":"pear/archive_tar","vulnerableRanges":["<1.4.11"],"patched":["1.4.11"],"provenance":"source","from":"GHSA"},{"id":"DRUPAL-CORE-2020-013","url":"https://osv.dev/vulnerability/DRUPAL-CORE-2020-013","severity":null,"ecosystem":"Packagist","package":"drupal/core","vulnerableRanges":[">=8.0.0, <8.8.12",">=8.9.0, <8.9.10",">=9.0.0, <9.0.9"],"patched":["8.8.12","8.9.10","9.0.9"],"provenance":"source","from":"OSV"}],"euvd":{"id":"EUVD-2021-0783","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2021-0783","exploited":true,"exploitedSince":"2022-08-25","provenance":"source"},"exploits":[],"exploitSources":{"metasploit":[{"name":"PEAR Archive_Tar 1.4.10 Arbitrary File Write","module":"exploit/multi/fileformat/archive_tar_arb_file_write","type":"exploit","disclosureDate":"2020-11-17","url":"https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/multi/fileformat/archive_tar_arb_file_write.rb"}],"first":{"date":"2020-11-17","source":"Metasploit","url":"https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/multi/fileformat/archive_tar_arb_file_write.rb"},"provenance":"source"},"exploitRefs":["http://packetstormsecurity.com/files/161095/PEAR-Archive_Tar-Arbitrary-File-Write.html","https://github.com/pear/Archive_Tar/issues/33"],"flow":[{"stage":"exploitation","techniques":["T1204.002"],"provenance":"ai"},{"stage":"primary","techniques":["T1005"],"provenance":"ai"}],"timeline":[{"date":"2020-11-17","kind":"exploit-public","label":"First public exploit: Metasploit","url":"https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/multi/fileformat/archive_tar_arb_file_write.rb","provenance":"source"},{"date":"2020-11-19","kind":"published","label":"Published (NVD)","url":"https://nvd.nist.gov/vuln/detail/CVE-2020-28949","provenance":"source"},{"date":"2022-08-25","kind":"exploited-reported","label":"Exploitation first reported (VulnCheck KEV evidence)","url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","provenance":"source"},{"date":"2022-08-25","kind":"kev","label":"Added to CISA KEV","url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","provenance":"source"},{"date":"2022-08-25","kind":"euvd-exploited","label":"ENISA EUVD: exploited","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2021-0783","provenance":"source"}],"speed":{"daysToPublicExploit":null,"firstExploitFrom":"Metasploit","daysToKev":644},"priority":{"score":78.4,"factors":[{"name":"In a KEV catalog","points":35.0,"detail":"listed in CISA KEV and VulnCheck KEV"},{"name":"Recent KEV listing","points":0.0,"detail":"added 1526 days ago"},{"name":"Known ransomware use","points":10.0,"detail":"CISA KEV and VulnCheck KEV: Known"},{"name":"EPSS percentile","points":19.94,"detail":"percentile 0.9970"},{"name":"Named in threat reports","points":0.0,"detail":"0 reports"},{"name":"Public exploit code","points":5.0,"detail":"2 NVD references tagged Exploit; 1 Metasploit module"},{"name":"Mentioned in OTX pulses","points":3.0,"detail":"50 pulses"},{"name":"CVSS severity","points":5.46,"detail":"base score 7.8"},{"name":"End-of-life product","points":0.0,"detail":"supported or unknown"}]},"lineage":{"familyId":"fam-pear-archive-tar-cve-2018-1000888","parents":[{"from":"CVE-2018-1000888","to":"CVE-2020-28949","relation":"successor","confidence":"high","kind":"lineage","evidence":[{"kind":"version-step","provenance":"source","package":"Packagist:pear/archive_tar","fromFixed":"1.4.4","toFixed":"1.4.11","daysApart":693},{"kind":"same-code","provenance":"machine","files":["Archive/Tar.php"],"commits":["https://github.com/pear/Archive_Tar/commit/59ace120ac5ceb5f0d36e40e48e1884de1badf76","https://github.com/pear/Archive_Tar/commit/0670a05fdab997036a3fc3ef113b8f5922e574da"],"basis":"shared function","functions":["_tarRecToSize"]}]}],"packageHistory":[{"cve":"CVE-2006-0931","published":"2006-02-28","fixed":"1.3.2","kev":false},{"cve":"CVE-2018-1000888","published":"2018-12-27","fixed":"1.4.4","kev":false},{"cve":"CVE-2020-28948","published":"2020-11-19","fixed":"1.4.11","kev":false},{"cve":"CVE-2020-28949","published":"2020-11-19","fixed":"1.4.11","kev":true},{"cve":"CVE-2020-36193","published":"2021-01-18","fixed":"1.4.13","kev":true,"link":{"from":"CVE-2020-28949","to":"CVE-2020-36193","relation":"successor","confidence":"high","kind":"sequence","evidence":[{"kind":"version-step","provenance":"source","package":"Packagist:pear/archive_tar","fromFixed":"1.4.11","toFixed":"1.4.13","daysApart":60},{"kind":"same-code","provenance":"machine","files":["Archive/Tar.php"],"commits":["https://github.com/pear/Archive_Tar/commit/0670a05fdab997036a3fc3ef113b8f5922e574da","https://github.com/pear/Archive_Tar/commit/cde460582ff389404b5b3ccb59374e9b389de916"],"basis":"shared file"}]}},{"cve":"CVE-2021-32610","published":"2021-07-27","fixed":"1.4.14","kev":false}],"package":"Packagist:pear/archive_tar"}}