A previously unreported memory-resident ARM64 malware named PEERSTITCH is being deployed by a suspected advanced threat actor. The malware exploits a path traversal flaw in the command line interpreter of Fortinet products, including FortiOS, FortiPAM, FortiProxy, and FortiSwitchManager.
The vulnerability, identified as CVE-2025-61624, has a CVSS score of 5.4. Exploitation of this flaw allows the threat actor to bypass checks on tagged VPN sessions, enabling the delivery of the PEERSTITCH malware.
By the numbers
- CVSS score of CVE-2025-61624
- 5.4
Sources and references
Original report
PEERSTITCH Malware Deployed via FortiOS Flaw Bypasses Checks on Tagged VPN Sessions
The Hacker News
Read on The Hacker News (opens in a new tab)Ref 00812QZF
Cite this
APA
Interestana AI Editorial. (2026, October 16). PEERSTITCH Malware Exploits FortiOS Flaw for ARM64 Attacks. Interestana. https://interestana.com/articles/peerstitch-malware-deployed-via-fortios-flaw-bypasses-checks-on-tagged-vpn-sessions-00812qzf
MLA
“PEERSTITCH Malware Exploits FortiOS Flaw for ARM64 Attacks.” Interestana, 16 Oct. 2026, interestana.com/articles/peerstitch-malware-deployed-via-fortios-flaw-bypasses-checks-on-tagged-vpn-sessions-00812qzf.
Chicago
Interestana AI Editorial. “PEERSTITCH Malware Exploits FortiOS Flaw for ARM64 Attacks.” Interestana, October 16, 2026. https://interestana.com/articles/peerstitch-malware-deployed-via-fortios-flaw-bypasses-checks-on-tagged-vpn-sessions-00812qzf.
BibTeX
@misc{interestana_00812qzf,
author = {{Interestana AI Editorial}},
title = {{PEERSTITCH Malware Exploits FortiOS Flaw for ARM64 Attacks}},
howpublished = {Interestana},
year = {2026},
month = oct,
url = {https://interestana.com/articles/peerstitch-malware-deployed-via-fortios-flaw-bypasses-checks-on-tagged-vpn-sessions-00812qzf},
note = {Summary of reporting by The Hacker News, https://thehackernews.com/2026/10/attackers-exploit-fortios-flaw-to.html}
}Credit the source
Original reporting: The Hacker News, “PEERSTITCH Malware Deployed via FortiOS Flaw Bypasses Checks on Tagged VPN Sessions”, https://thehackernews.com/2026/10/attackers-exploit-fortios-flaw-to.html(opens in a new tab)
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