CVE-2026-55497
Received Received - Intake

Memory Exhaustion in Cloudreve via Image Decoding

Publication date: 2026-07-31

Last updated on: 2026-07-31

Assigner: GitHub, Inc.

Description
Cloudreve is a self-hosted file management and sharing system. Prior to 4.17.0, the built-in thumbnail and avatar image decoders limit compressed file size but do not limit decoded pixel dimensions, allowing an authenticated user to submit a small PNG, JPEG, or GIF that triggers an unbounded allocation and terminates the Cloudreve process through fatal out-of-memory behavior. This issue is fixed in version 4.17.0.

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Meta Information

Published
2026-07-31
Last Modified
2026-07-31
Generated
2026-07-31
AI Q&A
2026-07-31
EPSS Evaluated
N/A
NVD
CVE-2026-55497
EUVD
EUVD-2026-51392

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
cloudreve cloudreve to 4.17.0 (exc)

Helpful Resources

Exploitability

CWE
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KEV
KEV Icon
CWE ID Description
CWE-409 The product does not handle or incorrectly handles a compressed input with a very high compression ratio that produces a large output.
CWE-770 The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.
CWE-400 The product does not properly control the allocation and maintenance of a limited resource.

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Executive Summary

Cloudreve before version 4.17.0 has a flaw in its image processing where thumbnail and avatar decoders do not restrict pixel dimensions after decompression. This allows an authenticated user to upload a small PNG, JPEG, or GIF that causes excessive memory consumption when decoded, leading to a denial of service via out-of-memory termination.

Detection Guidance

This vulnerability can be detected by checking the Cloudreve version installed on your system. If the version is below 4.17.0, the system is vulnerable. No specific commands are provided in the context to detect the vulnerability directly.

Impact Analysis

If you use Cloudreve versions before 4.17.0, an attacker with valid credentials could upload a malicious image file that crashes the Cloudreve service by consuming all available memory. This would disrupt file management and sharing operations for all users.

Compliance Impact

This vulnerability primarily causes denial-of-service by exhausting system memory, leading to complete unavailability of the Cloudreve service. For GDPR, this could impact availability of personal data processing. For HIPAA, it may disrupt access to protected health information systems. Both standards require availability controls, and this vulnerability violates those requirements by enabling service disruption.

Mitigation Strategies

Upgrade Cloudreve to version 4.17.0 or later to mitigate the vulnerability. Ensure no untrusted users have access to the system until the upgrade is completed.

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