CVE Intelligence
CISA KEV High Privilege escalation exploit reference

CVE-2023-28434 — MinIO Security Feature Bypass Vulnerability

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`.

Published Mar 22, 2023 · Updated Oct 13, 2026 · Sources: CISA Known Exploited Vulnerabilities, NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: GitHub_M

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

CISA KEV · Sep 19, 2023 Proofs of concept on GitHub · 1
How the score was calculated
  • Confirmed exploitation (CISA KEV)+35
  • Public exploit/PoC (github)+6
  • EPSS 7.9% (30-day exploitation probability)+14
  • Technical severity (high)+6

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Confirmed
CISA KEV, listed Sep 19, 2023
EPSS FIRST
7.92%
ahead of 95% of scored CVEs · Oct 14, 2026
Affects
Minio
Minio and 1 more
CVSS base
8.8
High · 4 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
Active
none · proof-of-concept · active
Automatable
No
can an attacker script the kill-chain steps
Technical impact
Total
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

  • Documented patch — github.com (NIST National Vulnerability Database)
  • Go Github.com/minio/minio: fixed in version 0.0.0-202303200415 — github.com (GitHub Security Advisories)

CISA required action CISA

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

US federal deadline: Oct 10, 2023 — passed 1101 day(s) ago

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Minio Minio, Go Github.com/minio/minio).
  2. Treat as emergency remediation: the CVE is in CISA KEV (confirmed exploitation).
  3. Apply the fixed version or the patch documented under Remediation.
  4. EPSS ahead of 95% of scored CVEs: prioritize it in the patch queue.
  5. Search available logs for exploit probes matching the vulnerability class (privilege escalation), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Minio Minio < 2023-03-20t20-16-18z Vulnerable NIST National Vulnerability Database
Minio Minio version < RELEASE.2023-03-20T20-16-18Z Vulnerable CVE Program (cve.org) e CISA ADP
Go Github.com/minio/minio < 0.0.0-202303200415 Vulnerable GitHub Security Advisories

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
8.8 CVSS 3.1 High 2.8 5.9 security-advisories@github.com via NIST National Vulnerability Database
8.8 CVSS 3.1 High 2.8 5.9 nvd@nist.gov via NIST National Vulnerability Database
8.8 CVSS 3.1 High — — GitHub, Inc. via GitHub Security Advisories
8.8 CVSS 3.1 High — — GitHub_M via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (score shown at the top: nvd@nist.gov)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-269 · Improper Privilege Management

Other CVEs with this weakness →

CISA KEV details CISA

CISA lists a CVE once it has evidence of exploitation against real targets.

Listed
Sep 19, 2023
Federal deadline
Oct 10, 2023
passed 1101 day(s) ago
Ransomware use
Unknown

CISA records ransomware use only for campaigns it has confirmed, so “Unknown” means unrecorded, not ruled out. The deadline binds US federal agencies; for everyone else it is a reference date.

Public exploits, PoCs and detection templates

Public code that demonstrates or tests the flaw raises the odds of mass exploitation — and Nuclei templates help find vulnerable assets in your environment.

Proofs of concept on GitHub

Warning: public PoCs are sometimes disguised malware. Use them only for authorized testing in an isolated environment. This portal does not host exploit code — it only points to the sources.

EPSS over time FIRST

Oct 12, 2026 → Oct 14, 2026 · 3 reading(s) · max 7.92%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
  • Hunt retroactively in logs from before Sep 19, 2023 (KEV listing): exploitation may have started earlier.
web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

  • 2026
  • Fix documented
    Oct 13, 2026 · GitHub Security Advisories
  • Affected products added · go/github.com/minio/minio
    Oct 13, 2026 · GitHub Security Advisories
  • Affected products added · minio/minio
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • Fix documented
    Oct 13, 2026 · NIST National Vulnerability Database
  • Affected products added · minio/minio
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVSS changed · 8.8
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Analyzed
    Oct 13, 2026 · NIST National Vulnerability Database
  • Added to CISA KEV (detected)
    Oct 13, 2026 · CISA Known Exploited Vulnerabilities
  • Record created in this database
    Oct 13, 2026 · CISA Known Exploited Vulnerabilities
  • 2023
  • Added to CISA KEV catalog
    Sep 18, 2023 · CISA
  • CVE published
    Mar 22, 2023 · GitHub_M

Source activity

Repeated readings are counted rather than listed.

  • 2× References added · Oct 13, 2026 – Oct 13, 2026
  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

6 on the record

Elsewhere on this site

Minio
every CVE for this vendor
2023-09
what else CISA listed that month
Privilege escalation
same class
CWE-269
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-42600 MinIO: Path Traversal via msgpack Body in `ReadMultiple` Storage-REST Endpoint May 11, 2026
  • CVE-2026-40344 MinIO has an Unauthenticated Object Write via Missing Signature Verification in Unsigned-Trailer Uploads Apr 21, 2026
  • CVE-2026-41145 MinIO has an Unauthenticated Object Write via Query-String Credential Signature Bypass in Unsigned-Trailer Uploads Apr 21, 2026
  • CVE-2026-39414 MinIO affected a DoS via Unbounded Memory Allocation in S3 Select CSV Parsing Apr 8, 2026
  • CVE-2026-34204 MinIO is Vulnerable to SSE Metadata Injection via Replication Headers Mar 31, 2026
  • CVE-2026-33419 MinIO: LDAP login brute-force via user enumeration and missing rate limit Mar 24, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2023-28434 is "MinIO Security Feature Bypass Vulnerability", rated High. It affects Minio (Minio); versions are in the scope table. It is in CISA KEV: there is evidence of real-world exploitation. CVSS 8.8 describes technical severity. EPSS 7.92% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

Comments

Moderated technical discussion. Read the community guidelines.

No comments yet.

Sign in or create an account to comment and suggest corrections.