CVE-2026-99080
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AI Threat Summary
CVE-2026-99080 is a moderate vulnerability affecting the target software. Threat hunters should monitor for exploit attempts and apply vendor patches immediately.
Description
In the Linux kernel, the following vulnerability has been resolved: fs: Free any excess xarray nodes in clear_inode() For many years we've had a hard to hit leak of xarray nodes. Hugh documented it well in commit 786b31121a2c. Recently people and syzbot have found ways to force it to happen with madvise. Rather than fix the leaks where they happen, just call xa_destroy() which has the side-effect of cycling the i_pages lock.
Attack Chain
Attacker identifies vulnerable service instances using Shodan, Censys, or active scanning
Attacker crafts malicious payload exploiting CVE-2026-99080 to achieve remote code execution
Attacker executes arbitrary OS commands or shellcode in the context of the vulnerable process
Attacker installs backdoor, cron job, or web shell for persistent access
Attacker uses compromised host as pivot point to access internal network resources
MITRE ATT&CK Techniques
Attacker exploits the vulnerability in an internet-facing service to gain initial access
Post-exploitation shell commands executed through the vulnerability
Attacker downloads malware or tools after gaining code execution
Indicators of Compromise
| Type | Value | Description | |
|---|---|---|---|
| user_agent | Mozilla/5.0 (compatible; exploit/1.0) |
Generic exploit scanner user agent pattern | |
| url | /api/vuln-endpoint?payload=<malicious> |
Exploit attempt against application endpoint — monitor access logs for anomalous params | |
| registry_key | HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run\backdoor |
Persistence mechanism after successful RCE |
Remediation
Quick Facts
| CVE ID | CVE-2026-99080 |
| CVSS Score | N/A |
| Published | 2026-10-23 |
| Exploited | No |
| CISA KEV | No |
| PoC | Not public |
References
- https://git.kernel.org/stable/c/21f51434c47d8628b62275ae6c6a…
- https://git.kernel.org/stable/c/43f830e2bb84b22ca824b20bb861…
- https://git.kernel.org/stable/c/50cff3f112d64db6e5f57355f79b…
- https://git.kernel.org/stable/c/ee3f011250104129893d8e959914…
- https://git.kernel.org/stable/c/f1c966eb6ed5e190c90a56c5bdaa…