zip:unzip/1,2 and zip:extract/1,2 validate entry paths using zip:check_dir_level/2, which tracks directory depth as a running integer counter: .. decrements it, normal path components increment it. The caller rejects only paths where the final counter value is less than zero. A path such as ../x/y causes the counter to go negative mid-traversal then recover to zero, passing validation while resolving to a location outside the extraction directory when joined with the current working directory via add_cwd.
This vulnerability is associated with program file lib/stdlib/src/zip.erl.
This issue affects OTP from OTP 27.1 before OTP 29.0.4, OTP 28.5.0.4 and OTP 27.3.4.15, corresponding to stdlib from 6.1 before 8.0.3, 7.3.0.1 and 6.2.2.4.
"}],"value":"Relative Path Traversal vulnerability in Erlang OTP (stdlib zip module) allows writing files outside the intended extraction directory via a crafted zip archive.\n\nzip:unzip/1,2 and zip:extract/1,2 validate entry paths using zip:check_dir_level/2, which tracks directory depth as a running integer counter: .. decrements it, normal path components increment it. The caller rejects only paths where the final counter value is less than zero. A path such as ../x/y causes the counter to go negative mid-traversal then recover to zero, passing validation while resolving to a location outside the extraction directory when joined with the current working directory via add_cwd.\n\nThis vulnerability is associated with program file lib/stdlib/src/zip.erl.\n\nThis issue affects OTP from OTP 27.1 before OTP 29.0.4, OTP 28.5.0.4 and OTP 27.3.4.15, corresponding to stdlib from 6.1 before 8.0.3, 7.3.0.1 and 6.2.2.4."}],"impacts":[{"capecId":"CAPEC-139","descriptions":[{"lang":"en","value":"CAPEC-139 Relative Path Traversal"}]}],"metrics":[{"cvssV4_0":{"attackComplexity":"LOW","attackRequirements":"NONE","attackVector":"LOCAL","baseScore":4.8,"baseSeverity":"MEDIUM","privilegesRequired":"NONE","subAvailabilityImpact":"LOW","subConfidentialityImpact":"NONE","subIntegrityImpact":"LOW","userInteraction":"PASSIVE","vectorString":"CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:L/SC:N/SI:L/SA:L","version":"4.0","vulnAvailabilityImpact":"LOW","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"LOW"},"format":"CVSS","scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-23","description":"CWE-23 Relative Path Traversal","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-07-27T16:10:02.280Z","orgId":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db","shortName":"EEF"},"references":[{"tags":["vendor-advisory","related"],"url":"https://github.com/erlang/otp/security/advisories/GHSA-rf72-wp7h-jg3x"},{"tags":["related"],"url":"https://cna.erlef.org/cves/CVE-2026-47078.html"},{"tags":["related"],"url":"https://osv.dev/vulnerability/EEF-CVE-2026-47078"},{"tags":["x_version-scheme"],"url":"https://www.erlang.org/doc/system/versions.html#order-of-versions"},{"tags":["patch"],"url":"https://github.com/erlang/otp/commit/8a933c9c7835b06776d31d17b79b7336627d887a"}],"source":{"discovery":"EXTERNAL"},"title":"Relative path traversal in zip:unzip/zip:extract via check_dir_level depth-counter bypass","x_generator":{"engine":"cvelib 1.8.0"}}},"cveMetadata":{"assignerOrgId":"6b3ad84c-e1a6-4bf7-a703-f496b71e49db","assignerShortName":"EEF","cveId":"CVE-2026-47078","datePublished":"2026-07-27T15:03:50.929Z","dateReserved":"2026-05-18T17:28:10.319Z","dateUpdated":"2026-07-27T16:10:02.280Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"}