# CVE-2026-39414: MinIO affected a DoS via Unbounded Memory Allocation in S3 Select CSV Parsing > Authenticated users can crash MinIO servers by uploading CSV files without newlines, causing memory exhaustion during S3 Select processing. - **Severity:** High 7.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`) - **Exploited in the wild:** Not known - **Login needed:** Any signed-in user - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 8 Apr 2026 - **Updated:** 9 Apr 2026 - **Also known as:** GHSA-h749-fxx7-pwpg, GO-2026-5415 ## What is CVE-2026-39414? CVE-2026-39414 is a high-severity denial of service vulnerability in minio, published on 8 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim. ### Official description MinIO is a high-performance object storage system. From RELEASE.2018-08-18T03-49-57Z to before RELEASE.2025-12-20T04-58-37Z, 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. Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling) ## Which versions are affected by CVE-2026-39414? 3 open source packages ship an affected version, including github.com/minio/minio. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `github.com/minio/minio` | Go | From 0.0.0-20180815103019-7c14cdb60e53 | None | | `github.com/minio/minio` | Go | From 0.0.0-20180815103019-7c14cdb60e53 | None | | `github.com/minio/minio` | Go | From 0.0.0-20180815103019-7c14cdb60e53 | None | Products: Minio Minio. ## How do I fix CVE-2026-39414? Upgrade to a fixed version. ## Is CVE-2026-39414 being exploited? There is no known exploitation of CVE-2026-39414 in the wild and no public exploit code. ## Other vulnerabilities in minio - [CVE-2023-28434](https://insights.sbomify.com/CVE-2023-28434/): MinIO Security Feature Bypass (high 8.8, exploited in the wild) - [CVE-2023-28432](https://insights.sbomify.com/CVE-2023-28432/): MinIO Information Disclosure (high 7.5, exploited in the wild) - [CVE-2020-11012](https://insights.sbomify.com/CVE-2020-11012/): Authentication bypass MinIO Admin API (critical 9.3) - [CVE-2026-33322](https://insights.sbomify.com/CVE-2026-33322/): MinIO: JWT Algorithm Confusion in OIDC Authentication (critical 9.2) - [CVE-2026-33419](https://insights.sbomify.com/CVE-2026-33419/): MinIO: LDAP login brute-force via user enumeration and missing rate limit (critical 9.1) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-39414 and fix it if it is affected. What it is: CVE-2026-39414 is a high-severity denial of service vulnerability in minio, published on 8 Apr 2026. Any signed-in user can exploit it over the network, with no action from the victim. Exploitation: There is no known exploitation of CVE-2026-39414 in the wild and no public exploit code. Affected packages and fixed versions: - github.com/minio/minio (Go): affected from 0.0.0-20180815103019-7c14cdb60e53; no fix listed - github.com/minio/minio (Go): affected from 0.0.0-20180815103019-7c14cdb60e53; no fix listed - github.com/minio/minio (Go): affected from 0.0.0-20180815103019-7c14cdb60e53; no fix listed Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2026-39414/ (Markdown: https://insights.sbomify.com/CVE-2026-39414/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-39414 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-39414 - OSV: https://osv.dev/vulnerability/CVE-2026-39414 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-39414/ Summaries are generated and may contain mistakes; the official description above is the record.