- Published
- Source
- Security Affairs
- Vulnerabilities
- 1 CVE Exploited
Mandiant and GTIG detail active exploitation of a Citrix NetScaler zero-day, deploying custom web shells WHIPSHOT and SLAPSHOT for root access. Mandiant and Google Threat Intelligence Group caught active exploitation of a zero-day in Citrix NetScaler ADC and Gateway appliances in late September 2026. The bug, tracked as CVE-2026-88772 (CVSS score of 9.5), has been…
If you run the affected product
- Find every instance – especially the ones reachable from the internet.
- Apply the vendor's patch or mitigation now: exploited flaws are fixed in days, not at the next patch cycle.
- Then check for signs it was used before you patched: web shells, new accounts, unusual outbound traffic.
More helpCISA's Known Exploited Vulnerabilities catalogue (opens in a new tab)
The vulnerabilities in this story
CVE-2026-88772 in the NVD (opens in a new tab)
- CVSS8.1High
- EPSS1.3%chance of exploitation in 30 days
- CISA KEVExploitedon the list since 27 Sep
Exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog (CC0). Exploit prediction: EPSS by FIRST. This product uses the NVD API but is not endorsed or certified by the NVD.
Defender’s notebook
The attacker technique behind this story, in MITRE’s terms – and what to check in your own estate.
External Remote Services
Persistence, Initial AccessWhat a defender checks
- List every VPN, remote desktop and remote-access gateway you expose.
- Require MFA on all of them, and keep them patched.
- Alert on sign-ins from new countries, networks or devices.
Build the skillBlue Team Engineer · Network Security Engineering
© 2026 The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation. MITRE ATT&CK and ATT&CK are registered trademarks of The MITRE Corporation.
MyCyberWay training
Blue Team Analyst
Every story here started as an alert. Learn to triage them.
Our Blue Team Analyst programme prepares you for a first SOC role: 26 live classes in UK hours, an alert queue worked in Microsoft Sentinel, and a full SOC shift simulation at the end. No security experience needed to start.
- Triage and KQL in Microsoft Sentinel
- Identity, endpoint, email and network investigations
- A verifiable digital badge
Headlines and short summaries only, except where a public body publishes under an open licence. Every story links to its publisher, who owns it. MyCyberWay does not edit or endorse third-party reporting.
