{"id":"CVE-2023-28434","aliases":["GHSA-2pxw-r47w-4p8c","BIT-minio-2023-28434"],"title":"Privilege Escalation on Linux/MacOS","summary":"Privilege Escalation on Linux/MacOS","severity":"high","cvss":8.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:H","exploited":true,"vendor":"minio","product":"github.com/minio/minio","ecosystem":"go","affected":["github.com/minio/minio < 0.0.0-202303200415"],"patched":["github.com/minio/minio 0.0.0-202303200415"],"published":"2023-09-05","updated":"2026-09-10","sourceUpdated":"2026-09-10T03:50:03.189234471Z","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-2pxw-r47w-4p8c","references":[{"url":"https://github.com/minio/minio/security/advisories/GHSA-2pxw-r47w-4p8c"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2023-28434"},{"url":"https://github.com/minio/minio/pull/16849"},{"url":"https://github.com/minio/minio/commit/67f4ba154a27a1b06e48bfabda38355a010dfca5"},{"url":"https://github.com/minio/minio"},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-28434"}],"tags":["osv","go","kev","in-the-wild","exploit-available"],"epss":0.07917,"epssPercentile":0.94461,"kev":true,"kevDateAdded":"2023-09-19","kevDueDate":"2023-10-10","kevRansomware":false,"exploits":{"github":1,"githubRepos":["https://github.com/AbelChe/evil_minio"],"checkedAt":"2026-09-23T07:13:25.112Z"},"exploitAvailable":true,"ingestedAt":"2026-09-12T03:13:01.746Z","slug":"CVE-2023-28434","body":"## Overview\n\n### Impact\nAn attacker can use crafted requests to bypass metadata bucket name checking and put an object into any bucket while processing `PostPolicyBucket`. To carry out this attack, the attacker requires credentials with `arn:aws:s3:::*` permission, as well as enabled Console API access.\n\n### Patches\n```\ncommit 67f4ba154a27a1b06e48bfabda38355a010dfca5\nAuthor: Aditya Manthramurthy <donatello@users.noreply.github.com>\nDate:   Sun Mar 19 21:15:20 2023 -0700\n\n    fix: post policy request security bypass (#16849)\n```\n\n### Workarounds\nBrowser API access must be enabled turning off `MINIO_BROWSER=off` allows for this workaround.\n\n### References\nThe vulnerable code:\n```go\n// minio/cmd/generic-handlers.go\nfunc setRequestValidityHandler(h http.Handler) http.Handler {\n  return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {\n    // ...\n    // For all other requests reject access to reserved buckets\n    bucketName, _ := request2BucketObjectName(r)\n    if isMinioReservedBucket(bucketName) || isMinioMetaBucket(bucketName) {\n      if !guessIsRPCReq(r) && !guessIsBrowserReq(r) && !guessIsHealthCheckReq(r) && !guessIsMetricsReq(r) && !isAdminReq(r) && !isKMSReq(r) {\n        if ok {\n          tc.FuncName = \"handler.ValidRequest\"\n          tc.ResponseRecorder.LogErrBody = true\n        }\n        writeErrorResponse(r.Context(), w, errorCodes.ToAPIErr(ErrAllAccessDisabled), r.URL)\n        return\n      }\n    }\n    // ...\n```\n\n## Affected packages\n\n- `github.com/minio/minio < 0.0.0-202303200415`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `github.com/minio/minio 0.0.0-202303200415`","depth":"abyssal","depthScore":75,"depthScoreParts":{"impact":48.4,"likelihood":1.6,"exploitation":25,"ransomware":0},"changes":[]}