CVE-2026-42886: CWE-409: Improper Handling of Highly Compressed Data (Data Amplification) in advplyr audiobookshelf
CVE-2026-42886 is a medium severity vulnerability in advplyr's audiobookshelf versions prior to 2. 33. 2. It involves improper handling of highly compressed data in the POST /api/backups/upload endpoint. Specifically, the server decompresses a details entry from an uploaded ZIP file entirely into memory without limiting the decompressed size. This allows an admin user to upload a crafted ZIP file that decompresses to consume excessive memory, potentially crashing the server due to out-of-memory conditions. The vulnerability is fixed in version 2. 33. 2.
AI Analysis
Technical Summary
The audiobookshelf server prior to version 2.33.2 has a vulnerability (CWE-409) in its backup upload API endpoint where the details entry of an uploaded ZIP file is decompressed fully into memory without size limits. The upload middleware also lacks file size restrictions. An attacker with admin privileges can exploit this by uploading a specially crafted ZIP file with a highly compressed details entry that expands to hundreds of megabytes or gigabytes, causing the server process to crash due to memory exhaustion. This is a denial-of-service condition caused by improper handling of compressed data. The issue is resolved in version 2.33.2.
Potential Impact
This vulnerability can cause a denial-of-service (DoS) by crashing the audiobookshelf server process through out-of-memory conditions. There is no impact on confidentiality or integrity as per the available data. Exploitation requires admin privileges and no user interaction is needed. No known exploits are reported in the wild.
Mitigation Recommendations
A fix is available in audiobookshelf version 2.33.2. Users should upgrade to this version or later to remediate the vulnerability. Until upgraded, administrators should avoid uploading backup ZIP files from untrusted sources. Patch status is confirmed by the vendor stating the issue is fixed in 2.33.2.
CVE-2026-42886: CWE-409: Improper Handling of Highly Compressed Data (Data Amplification) in advplyr audiobookshelf
Description
CVE-2026-42886 is a medium severity vulnerability in advplyr's audiobookshelf versions prior to 2. 33. 2. It involves improper handling of highly compressed data in the POST /api/backups/upload endpoint. Specifically, the server decompresses a details entry from an uploaded ZIP file entirely into memory without limiting the decompressed size. This allows an admin user to upload a crafted ZIP file that decompresses to consume excessive memory, potentially crashing the server due to out-of-memory conditions. The vulnerability is fixed in version 2. 33. 2.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The audiobookshelf server prior to version 2.33.2 has a vulnerability (CWE-409) in its backup upload API endpoint where the details entry of an uploaded ZIP file is decompressed fully into memory without size limits. The upload middleware also lacks file size restrictions. An attacker with admin privileges can exploit this by uploading a specially crafted ZIP file with a highly compressed details entry that expands to hundreds of megabytes or gigabytes, causing the server process to crash due to memory exhaustion. This is a denial-of-service condition caused by improper handling of compressed data. The issue is resolved in version 2.33.2.
Potential Impact
This vulnerability can cause a denial-of-service (DoS) by crashing the audiobookshelf server process through out-of-memory conditions. There is no impact on confidentiality or integrity as per the available data. Exploitation requires admin privileges and no user interaction is needed. No known exploits are reported in the wild.
Mitigation Recommendations
A fix is available in audiobookshelf version 2.33.2. Users should upgrade to this version or later to remediate the vulnerability. Until upgraded, administrators should avoid uploading backup ZIP files from untrusted sources. Patch status is confirmed by the vendor stating the issue is fixed in 2.33.2.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-04-30T18:49:06.712Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a028779cbff5d86108b80b9
Added to database: 5/12/2026, 1:50:49 AM
Last enriched: 5/12/2026, 2:09:02 AM
Last updated: 5/12/2026, 3:45:49 AM
Views: 2
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
External Links
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.