Out-of-bounds write in MapServer - #VU147317
Published: September 7, 2026
Vulnerability identifier: #VU147317
CSH Severity: High
CVSS v4: 8.8 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-787
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to a heap-based out-of-bounds write in FlatGeobuf PackedRTree::streamSearch when processing a crafted FlatGeobuf file. A remote attacker can provide a crafted FlatGeobuf file with an unchecked nodeItem.offset value to cause a denial of service.
The issue is reachable during R-Tree traversal when the query bounding box overlaps but is not contained within the layer's declared extent.
Affected software
MapServer
Remediation
Install security update from vendor's website.
MapServer - update to 8.6.6