CVE-2026-41309
CWE-400Published: April 24, 2026· Updated: Apr 29, 2026
Official Description
Open Source Social Network (OSSN) is open-source social networking software developed in PHP. Versions prior to 9.0 are vulnerable to resource exhaustion. An attacker can upload a specially crafted image with extreme pixel dimensions (e.g., $10000 \times 10000$ pixels). While the compressed file size on disk may be small, the server attempts to allocate significant memory and CPU cycles during the decompression and resizing process, leading to a Denial of Service (DoS) condition. It is highly recommended to upgrade to OSSN 9.0. This version introduces stricter validation of image dimensions and improved resource management during the processing phase. Those who cannot upgrade immediately can mitigate the risk by adjusting their `php.ini` settings to strictly limit `memory_limit` and `max_execution_time` and/or implementing a client-side and server-side check on image headers to reject files exceeding reasonable pixel dimensions (e.g., $4000 \times 4000$ pixels) before processing begins.
Technical Analysis
CVE-2026-41309 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in availability disruption (denial of service), with a CVSS base score of 8.2.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
All References (3)
Quick Facts
Related CVEs (CWE-400)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-41309 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts