How severe is CVE-2026-39414?

No CVSS score has been assigned to CVE-2026-39414 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-39414?

CVE-2026-39414 affects the following packages: github.com/minio/minio (Go). Ecosystems affected: Go.

How do I fix CVE-2026-39414?

No patched version of github.com/minio/minio has shipped for CVE-2026-39414 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.

How do I detect CVE-2026-39414 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/minio/minio, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-39414 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against CVE-2026-39414?

O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-39414 can be triaged on real exposure rather than presence alone.

Is CVE-2026-39414 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-39414 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-39414?

CVE-2026-39414 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 41th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-39414?

CVE-2026-39414 is classified as CWE-770 (CWE-770). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-39414 published, and has it been updated?

CVE-2026-39414 was published on April 8, 2026 and was last updated on August 12, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹 Go

Not in CISA KEV

CVE-2026-39414 — minio

Fix: minio/minio@7c14cdb

CVE-2026-39414 is a CWE-770 vulnerability in github.com/minio/minio. No vendor fix is recorded yet; mitigation options are listed below.

MinIO affected a DoS via Unbounded Memory Allocation in S3 Select CSV Parsing

Also known asBIT-minio-2026-39414GHSA-h749-fxx7-pwpgGO-2026-5415

Published

Apr 8, 2026

Updated

Aug 12, 2026

Affected

1 pkg

Patched

See advisory

Exploits

None indexed

Exploitation data as of Sep 21, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-39414.

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs41th percentile — riskier than 41% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Real-World Exposure

1 pkg affected

🐹github.com/minio/minio

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

Impact

What kind of vulnerability is it? Who is impacted?

MinIO's S3 Select feature is vulnerable to memory exhaustion when processing CSV files containing lines longer than available memory. The CSV reader's nextSplit() function calls bufio.Reader.ReadBytes('\n') with no size limit, buffering the entire input in memory until a newline is found. A CSV file with no newline characters causes the entire contents to be read into a single allocation, leading to an OOM crash of the MinIO server process.

This is exploitable by any authenticated user with s3:PutObject and s3:GetObject permissions. The attack is especially practical when combined with compression: a ~2 MB gzip-compressed CSV can decompress to gigabytes of data without newlines, allowing a small upload to cause large memory consumption on the server. However, compression is not required — a sufficiently large uncompressed CSV with no newlines triggers the same issue.

Affected component: internal/s3select/csv/reader.go, function nextSplit().

CWE: CWE-770 (Allocation of Resources Without Limits or Throttling)

Affected Versions

All MinIO releases are through the final release of the minio/minio open-source project.

The vulnerability was introduced in commit https://github.com/minio/minio/commit/7c14cdb60e53dbfdad2be644dfb180cab19fffa7, which added S3 Select support for CSV. The CSV reader has used unbounded line reads since this commit (originally via Go's stdlib encoding/csv.Reader, later via bufio.Reader.ReadBytes after a refactor in PR #8200.

The first affected release is RELEASE.2018-08-18T03-49-57Z.

Patches

Fixed in: MinIO AIStor RELEASE.2025-12-20T04-58-37Z

The fix replaces the unbounded bufio.Reader.ReadBytes('\n') call with a byte-at-a-time loop that caps line scanning at 128 KB (csvSplitSize). If no newline is found within this limit, the reader returns an error instead of continuing to buffer.

Binary Downloads

Platform	Architecture	Download
Linux	amd64	minio
Linux	arm64	minio
macOS	arm64	minio
macOS	amd64	minio
Windows	amd64	minio.exe

FIPS Binaries

Platform	Architecture	Download
Linux	amd64	minio.fips
Linux	arm64	minio.fips

Package Downloads

Format	Architecture	Download
DEB	amd64	minio_20251220045837.0.0_amd64.deb
DEB	arm64	minio_20251220045837.0.0_arm64.deb
RPM	amd64	minio-20251220045837.0.0-1.x86_64.rpm
RPM	arm64	minio-20251220045837.0.0-1.aarch64.rpm

Container Images

# Standard
docker pull quay.io/minio/aistor/minio:RELEASE.2025-12-20T04-58-37Z
podman pull quay.io/minio/aistor/minio:RELEASE.2025-12-20T04-58-37Z

# FIPS
docker pull quay.io/minio/aistor/minio:RELEASE.2025-12-20T04-58-37Z.fips
podman pull quay.io/minio/aistor/minio:RELEASE.2025-12-20T04-58-37Z.fips

Homebrew (macOS)

brew install minio/aistor/minio

Workarounds

Users of the open-source minio/minio project should upgrade to MinIO AIStor RELEASE.2025-12-20T04-58-37Z or later.

If upgrading is not immediately possible:

Disable S3 Select access via IAM policy. Deny the s3:GetObject action with a condition restricting s3:prefix on sensitive buckets, or more specifically, deny SelectObjectContent requests at a reverse proxy by blocking POST requests with ?select&select-type=2 query parameters.
Restrict PutObject permissions. Limit s3:PutObject grants to trusted principals to reduce the attack surface. Note: this reduces risk but does not eliminate the vulnerability since any authorized user can exploit it.

References

Introducing commit: 7c14cdb60 (PR #6127)
MinIO AIStor

Affected Packages

1 total

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/minio/minio`	≥ 0.0.0-20180815103019-7c14cdb60e53	No fix

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/minio/minio, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Remediation status
No patched version of github.com/minio/minio has shipped for CVE-2026-39414 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-39414 can be triaged on real exposure rather than presence alone.

Tailored to CVE-2026-39414. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Impact _What kind of vulnerability is it? Who is impacted?_ MinIO's S3 Select feature is vulnerable to memory exhaustion when processing CSV files containing lines longer than available memory. The CSV reader's `nextSplit()` function calls `bufio.Reader.ReadBytes('\n')` with no size limit, buffering the entire input in memory until a newline is found. A CSV file with no newline characters causes the entire contents to be read into a single allocation, leading to an OOM crash of the MinIO server process. This is exploitable by any authenticated user with `s3:PutObject` and `s3:GetObj

O3 Security · Impact-Aware SCA

Is CVE-2026-39414 in your dependencies?

O3 Security finds CVE-2026-39414 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

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