CVE-2026-42886 Audiobookshelf: Memory amplification DoS via oversized compressed details entry in backup upload
An admin user can crash the Audiobookshelf server by uploading a crafted ZIP file that causes memory exhaustion during decompression.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-42886?
CVE-2026-42886 is a medium-severity denial of service vulnerability in advplyr audiobookshelf, published on 11 May 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
Audiobookshelf is a self-hosted audiobook and podcast server. Prior to 2.32.2, the POST /api/backups/upload endpoint decompresses the details entry from an uploaded .audiobookshelf ZIP file entirely into memory using zip.entryData(), with no limit on the decompressed size. The upload middleware also has no file size limit. An admin user can upload a crafted ZIP containing a highly compressed details entry that, when decompressed, consumes hundreds of megabytes or gigabytes of memory, crashing the server process via out-of-memory. This vulnerability is fixed in 2.32.2.
Weakness: CWE-409
Which versions are affected by CVE-2026-42886?
How do I fix CVE-2026-42886?
No fix has been published for CVE-2026-42886 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-42886 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-42886 exists.
Sources
Also known as GHSA-4jq4-rvq8-j26h.