CVE-2023-28434

CRITICALNVD 8.89.0
EchelonGraph scoreHIGH confidence

“▲” beside the score: it is higher than NVD's CVSS score.

Score elevated to 9.0 because this CVE is listed on the CISA Known Exploited Vulnerabilities catalog (added 2023-09-19), indicating real-world exploitation has been confirmed by US federal agencies. NVD baseline CVSS 8.8 retained for reference. The 9.0 is the floor for confirmed exploitation, not an impact rating: this CVE's impact severity (EG Severity) is CVSS 8.8 HIGH under GitHub Security Advisory CVSS. Confidence: HIGH.

Triggered by: CISA KEV (actively exploited)
Sources: CISA Known Exploited Vulnerabilities catalog, EPSS, GitHub Security Advisory, NVD CVSS v3
Trending — 3 sources updated this weekExploited in the wild

Also known asEUVD-2023-2395 (ENISA EUVD) · GHSA-2pxw-r47w-4p8c (GitHub Security Advisories)Source: ENISA EUVD

9.0EG
EchelonGraph verdictPatch nowTreat as an emergency — this is being exploited.
  • Actively exploited in the wild (CISA-KEV) — the reason this is sooner than the SSVC decision on this page at low or medium mission impact
CISA-KEV: ExploitedEPSS PROB: 7.9%CVSS: 8.8Exploit: Public PoCExposed services: Not assessed

A fix is available — apply it.

Minio is a Multi-Cloud Object Storage framework. Prior to RELEASE.2023-03-20T20-16-18Z, an 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. This issue has been patched in RELEASE.2023-03-20T20-16-18Z. As a workaround, enable browser API access and turn off MINIO_BROWSER=off.

CVSS v3
8.8
EG Score
9.0CRITICALhigh confidence
EG Risk
80
EG Risk 80/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity88% × 45%
Impact severity (EG Severity): CVSS 8.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation100% × 40%
Fixed at 100% for a CISA KEV listing: EchelonGraph's rule.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low, Attend at medium and Act at high mission impact.
Exploitation active (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines at low, sooner than that at medium and as soon as possible at high mission impact.
EPSS PROB
7.9%
EPSS %ILE
94th
KEV
⚠ Exploited

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (9.0): severity, escalated by confirmed exploitation. This CVE's 9.0 is the CISA KEV floor for confirmed exploitation, not an impact rating: its impact severity (EG Severity) is CVSS 8.8 HIGH.

EG Severity
8.8 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
7.9% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-01). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
CISA KEV and EG-KEV Tier 1 (exploited in the wild)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Attend at medium mission impactTrack at low, Attend at medium and Act at high mission impact.CISA BOD 26-04: 3 days & forensic triage if the affected system is publicly exposed; 14 days if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low, Attend at medium and Act at high mission impact.

A fix is available. Apply it within your standard update timelines at low, sooner than that at medium and as soon as possible at high mission impact.

Exploitation active (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)3 days & forensic triage if the affected system is publicly exposed; 14 days if it is not.

The score's inputs: In CISA KEV yes (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

CISA required action“Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.”

Quoted verbatim from CISA's Known Exploited Vulnerabilities catalog. CISA directs it at US federal civilian executive branch agencies under Binding Operational Directive (BOD) 26-04, which replaced BOD 22-01 on 10 June 2026; it is not EchelonGraph's advice. CISA's notes: https://github.com/minio/minio/security/advisories/GHSA-2pxw-r47w-4p8c · https://nvd.nist.gov/vuln/detail/CVE-2023-28434

Published

March 22, 2023

Last Modified

February 26, 2026

Advisory Details (4)

Auto-updated Nov 2, 2026
⚠️ Actively exploited (CISA KEV, CISA Vulnrichment). Patch available. Sources: github_commit, github_pr, github, cisa.
CISA🔴 Active Exploitation

Known Exploited Vulnerabilities Catalog | CISA

Known Exploited Vulnerabilities Catalog | CISA. Listed in CISA Known Exploited Vulnerabilities catalog.

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-28434
GitHub advisoryMentions a patch (unverified)

Privilege Escalation on Linux/MacOS · Advisory · minio/minio · GitHub

https://github.com/minio/minio/security/advisories/GHSA-2pxw-r47w-4p8c
GitHub pull request

fix: post policy request security bypass

Fix merged in minio/minio PR #16849 on 2023-03-20 — awaiting tagged release

https://github.com/minio/minio/pull/16849
GitHub commit

commit 67f4ba154a27 (minio/minio)

Fix landed in minio/minio commit 67f4ba154a27 — awaiting tagged release

https://github.com/minio/minio/commit/67f4ba154a27a1b06e48bfabda38355a010dfca5

Patch Availability(1)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
gogithub.com/minio/minio @ 0.0.0-202303200415 (fixes < 0.0.0-202303200415)—ghsa

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(1 across 1 ecosystem)
Go(1)
PackageVulnerable rangeFix by version rangeDependents
github.com/minio/minio—
  • every version up to 0.0.0-202303200415: fixed in 0.0.0-202303200415
—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 17× in last 7d / 63× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 100 of 352 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 252 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-01 23:26 UTCEG score recompute
  2. 2026-11-01 23:25 UTCGHSA enrichmentGHSA-2pxw-r47w-4p8c · GitHub severity HIGH · GitHub CVSS 8.8
  3. 2026-11-01 16:30 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  4. 2026-11-01 08:21 UTCGHSA enrichmentGHSA-2pxw-r47w-4p8c · GitHub severity HIGH · GitHub CVSS 8.8
  5. 2026-11-01 08:21 UTCEG score recompute
  6. 2026-11-01 00:54 UTCEG score recompute
  7. 2026-10-31 16:29 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  8. 2026-10-31 02:23 UTCEG score recompute
  9. 2026-10-30 16:31 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  10. 2026-10-30 03:52 UTCEG score recompute
  11. 2026-10-29 16:30 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  12. 2026-10-29 05:21 UTCEG score recompute
  13. 2026-10-28 16:29 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  14. 2026-10-28 06:50 UTCEG score recompute
  15. 2026-10-27 16:29 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  16. 2026-10-27 08:19 UTCEG score recompute
  17. 2026-10-26 16:28 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  18. 2026-10-25 17:45 UTCEG score recompute
  19. 2026-10-25 16:29 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  20. 2026-10-25 11:17 UTCEG score recompute
  21. 2026-10-24 16:29 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  22. 2026-10-24 12:45 UTCEG score recompute
  23. 2026-10-23 16:29 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  24. 2026-10-23 14:15 UTCEG score recompute
  25. 2026-10-22 16:31 UTCEPSS rescoreEPSS 7.9% · 94th percentile
Show 75 more
  1. 2026-10-21 17:11 UTCEG score recompute
  2. 2026-10-21 16:29 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  3. 2026-10-20 18:40 UTCEG score recompute
  4. 2026-10-20 16:29 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  5. 2026-10-19 20:08 UTCEG score recompute
  6. 2026-10-19 16:29 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  7. 2026-10-18 21:36 UTCEG score recompute
  8. 2026-10-18 16:29 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  9. 2026-10-18 08:07 UTCEG score recompute
  10. 2026-10-17 23:05 UTCEG score recompute
  11. 2026-10-17 16:29 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  12. 2026-10-17 00:32 UTCEG score recompute
  13. 2026-10-16 16:35 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  14. 2026-10-16 02:00 UTCEG score recompute
  15. 2026-10-15 16:29 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  16. 2026-10-15 03:30 UTCEG score recompute
  17. 2026-10-14 16:29 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  18. 2026-10-14 04:58 UTCEG score recompute
  19. 2026-10-13 16:29 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  20. 2026-10-12 18:29 UTCEG score recompute
  21. 2026-10-12 16:30 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  22. 2026-10-11 19:12 UTCEG score recompute
  23. 2026-10-11 15:00 UTCEG score recompute
  24. 2026-10-11 13:45 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  25. 2026-10-10 22:07 UTCEG score recompute
  26. 2026-10-10 19:57 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  27. 2026-10-09 20:40 UTCEG score recompute
  28. 2026-10-09 20:05 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  29. 2026-10-08 19:25 UTCEG score recompute
  30. 2026-10-08 17:06 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  31. 2026-10-08 02:35 UTCEG score recompute
  32. 2026-10-07 23:45 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  33. 2026-10-06 16:54 UTCEG score recompute
  34. 2026-10-06 15:15 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  35. 2026-10-05 19:51 UTCEG score recompute
  36. 2026-10-05 17:41 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  37. 2026-10-03 17:22 UTCEG score recompute
  38. 2026-10-03 14:23 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  39. 2026-10-02 20:15 UTCEG score recompute
  40. 2026-10-02 16:23 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  41. 2026-10-01 23:12 UTCEG score recompute
  42. 2026-10-01 19:47 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  43. 2026-09-30 17:44 UTCEG score recompute
  44. 2026-09-30 15:01 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  45. 2026-09-29 16:30 UTCEG score recompute
  46. 2026-09-29 15:16 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  47. 2026-09-28 23:36 UTCEG score recompute
  48. 2026-09-28 15:11 UTCEG score recompute
  49. 2026-09-28 13:49 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  50. 2026-09-27 21:51 UTCCISA KEV update
  51. 2026-09-27 13:53 UTCEG score recompute
  52. 2026-09-27 13:42 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  53. 2026-09-26 16:46 UTCEG score recompute
  54. 2026-09-26 04:05 UTCEG score recompute
  55. 2026-09-26 00:22 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  56. 2026-09-25 19:35 UTCCISA KEV update
  57. 2026-09-25 14:55 UTCCISA KEV update
  58. 2026-09-24 19:31 UTCCISA KEV update
  59. 2026-09-24 14:14 UTCEG score recompute
  60. 2026-09-24 14:01 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  61. 2026-09-23 17:13 UTCEG score recompute
  62. 2026-09-23 13:45 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  63. 2026-09-22 19:36 UTCCISA KEV update
  64. 2026-09-22 15:58 UTCEG score recompute
  65. 2026-09-22 14:45 UTCEPSS rescoreEPSS 7.9% · 94th percentile
  66. 2026-09-21 23:10 UTCEG score recompute
  67. 2026-09-21 19:09 UTCCISA KEV update
  68. 2026-09-19 16:26 UTCEG score recompute
  69. 2026-09-18 19:25 UTCEG score recompute
  70. 2026-09-18 19:20 UTCCISA KEV update
  71. 2026-09-18 14:15 UTCCISA KEV update
  72. 2026-09-17 22:25 UTCEG score recompute
  73. 2026-09-16 16:57 UTCEG score recompute
  74. 2026-09-16 14:10 UTCCISA KEV update
  75. 2026-09-16 14:05 UTCEPSS rescoreEPSS 7.9% · 94th percentile

Publicly available exploits

(1 reference)

Public exploit code is referenced for this CVE (1 GitHub PoC). Defenders should treat patch urgency accordingly.

  • GitHub PoCAbelChe/evil_minio
    Published Mar 27, 2023

    EXP for CVE-2023-28434 MinIO unauthorized to RCE

    Open source ↗

Frequently asked(6)

What is CVE-2023-28434?
CVE-2023-28434 is a critical-severity vulnerability; its CVE record was published on March 22, 2023. Minio is a Multi-Cloud Object Storage framework. Prior to RELEASE.2023-03-20T20-16-18Z, an 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…
When was the CVE record for CVE-2023-28434 published?
The CVE record for CVE-2023-28434 was published on March 22, 2023. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of February 26, 2026; the record at its source may have been updated since.
Is CVE-2023-28434 actively exploited?
Yes. CISA added CVE-2023-28434 to the Known Exploited Vulnerabilities catalog on September 19, 2023, affecting MinIO MinIO. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate attention. A fix is available. Apply it.
What is the CVSS score of CVE-2023-28434?
CVE-2023-28434 has a CVSS v3 base score of 8.8 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.0 (CRITICAL).
Which products are affected by CVE-2023-28434?
CVE-2023-28434 affects MinIO MinIO. The affected packages EchelonGraph has on record, with version ranges, are listed in the Affected Packages section of this page.
How do I remediate CVE-2023-28434?
A fix for CVE-2023-28434 is available: update to the fixed version the vendor names in its advisory.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2023-28434

Explore →

Is Your Infrastructure Affected by CVE-2023-28434?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.