CVE-2026-39414
MinIO affected a DoS via Unbounded Memory Allocation in S3 Select CSV Parsing
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.
INFO
Published Date :
April 8, 2026, 9:16 p.m.
Last Modified :
July 24, 2026, 9:10 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update MinIO to a fixed release.
- Limit line lengths in CSV processing.
- Monitor server memory usage.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-39414.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-39414 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-39414
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-39414 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-39414 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Translated by [email protected]
Jul. 24, 2026
Action Type Old Value New Value Added Translation Title: MinIO, Description: MinIO es un sistema de almacenamiento de objetos de alto rendimiento. Desde RELEASE.2018-08-18T03-49-57Z hasta antes de RELEASE.2025-12-20T04-58-37Z, la característica S3 Select de MinIO es vulnerable al agotamiento de memoria al procesar archivos CSV que contienen líneas más largas que la memoria disponible. La función nextSplit() del lector de CSV llama a bufio.Reader.ReadBytes('\n') sin límite de tamaño, almacenando en búfer toda la entrada en memoria hasta que se encuentra un salto de línea. Un archivo CSV sin caracteres de salto de línea hace que todo el contenido se lea en una única asignación, lo que lleva a un fallo por OOM del proceso del servidor MinIO. Esto es explotable por cualquier usuario autenticado con permisos s3:PutObject y s3:GetObject. El ataque es especialmente práctico cuando se combina con compresión: un CSV comprimido con gzip de ~2 MB puede descomprimirse a gigabytes de datos sin saltos de línea, permitiendo que una pequeña carga cause un gran consumo de memoria en el servidor. Sin embargo, la compresión no es necesaria - un CSV sin comprimir suficientemente grande y sin saltos de línea desencadena el mismo problema. -
CVE Modified by [email protected]
Jun. 17, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'minio', 'product': 'minio', 'versions': [{'status': 'affected', 'version': '>= RELEASE.2018-08-18T03-49-57Z, < RELEASE.2025-12-20T04-58-37Z'}]}] -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 17, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-39414', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-04-09T14:57:40.322565Z'} -
Initial Analysis by [email protected]
Apr. 15, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Added CPE Configuration OR *cpe:2.3:a:minio:minio:*:*:*:*:*:*:*:* versions from (including) 2018-08-18t03-49-57z up to (including) 2025-10-15t17-29-55z Added Reference Type GitHub, Inc.: https://docs.min.io/enterprise/aistor-object-store/upgrade-aistor-server/community-edition Types: Product Added Reference Type GitHub, Inc.: https://github.com/minio/minio/commit/7c14cdb60e53dbfdad2be644dfb180cab19fffa7 Types: Patch Added Reference Type GitHub, Inc.: https://github.com/minio/minio/pull/8200 Types: Patch Added Reference Type GitHub, Inc.: https://github.com/minio/minio/security/advisories/GHSA-h749-fxx7-pwpg Types: Vendor Advisory -
New CVE Received by [email protected]
Apr. 08, 2026
Action Type Old Value New Value Added 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-770 Added Reference https://docs.min.io/enterprise/aistor-object-store/upgrade-aistor-server/community-edition Added Reference https://github.com/minio/minio/commit/7c14cdb60e53dbfdad2be644dfb180cab19fffa7 Added Reference https://github.com/minio/minio/pull/8200 Added Reference https://github.com/minio/minio/security/advisories/GHSA-h749-fxx7-pwpg