CVE-2026-887729.5Critical
CVE-2026-88772: Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability
Citrix NetScaler · ADC
Vendor fix available · Affected: Citrix NetScaler ADC · Exploitation: in CISA KEV since 27 Sep
ExploitationIn CISA KEV
- In CISA KEVCISA KEV catalogue27 Sep
- Exploited (reported): not seen
- Scanning observed: not seen
- Proof of concept public4 public GitHub repositories (unverified), listed by PoC-in-GitHub27 Sep
- Not established: not seen
76.6%probability of exploitation in the next 30 days
99th percentile
050100
Higher than 99% of scored CVEs
9.5CriticalCVSS 4.0
LowMediumHighCrit.
Federal deadline
CISA KEV · added 27 Sep · catalogue entry
Passed 41 days ago
DescriptionNVD
Vulnerability in Citrix NetScaler ADC and Citrix NetScaler Gateway. This issue affects ADC: before 14.1-73.37, before 13.1-64.23, before 14.1-73.37 FIPS, and before 13.1.37.279 FIPS and NDcPP; Gateway: before 14.1-73.37 and before 13.1-64.23 leading to Remote Code Execution or Denial of Service
What changed
- PoC-in-GitHub lists 4 public GitHub repositories (unverified) PoC-in-GitHub
- CISA added it to the KEV catalogue CISA
CISA required action
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
Coverage29 articles · 13 outlets
One row per outlet, in order of first report. First in our coverage: SecurityOnline, 27 Sep.
Quiet for 3 weekslast report 19 Oct29 articles13 outlets
- Sun 27 Sep, 18:30 UTC. SecurityOnline, first report. Citrix NetScaler Zero Days Exploited to Attack VPN Appliances. Cites a CVE in CISA KEV.
- Sun 27 Sep, 18:30 UTC. Security Affairs, its first report on the story. Citrix NetScaler Zero Days Exploited Against Unpatched Systems. Cites a CVE in CISA KEV.
- Sun 27 Sep, 20:47 UTC. CISA, its first report on the story. CISA Flags Actively Exploited Citrix NetScaler Flaws for Urgent Action. Cites a CVE in CISA KEV.
- Sun 27 Sep, 20:47 UTC. CISA. CISA Warns Attackers Are Exploiting Critical Citrix NetScaler Zero-Days. Cites a CVE in CISA KEV.
- Sun 27 Sep, 23:01 UTC. CISA. CISA Warns Attackers Are Exploiting Critical Citrix NetScaler Flaw. Cites a CVE in CISA KEV.
- Mon 28 Sep, 08:00 UTC. SecurityWeek, its first report on the story. Citrix Patches NetScaler Zero Days Exploited in Global Attacks. Cites a CVE in CISA KEV.
- Mon 28 Sep, 08:00 UTC. SOCRadar, its first report on the story. Citrix Patches NetScaler Zero Days Exploited in Global Attacks. Cites a CVE in CISA KEV.
- Mon 28 Sep, 08:35 UTC. Infosecurity, its first report on the story. Citrix NetScaler Zero Days Exploited in Attacks, Patch Now. Cites a CVE in CISA KEV.
- Mon 28 Sep, 09:47 UTC. Security Affairs. CISA Warns of Active Exploitation in Critical Citrix NetScaler Flaws. Cites a CVE in CISA KEV.
- Mon 28 Sep, 12:07 UTC. Rapid7, its first report on the story. Citrix NetScaler Zero Days Expose Appliances to Active RCE Attacks. Cites a CVE in CISA KEV.
- Mon 28 Sep, 13:21 UTC. NCSC, its first report on the story. UK Cyber Agency Urges Action on Exploited Citrix NetScaler Flaws. Cites a CVE in CISA KEV.
- Mon 28 Sep, 14:30 UTC. The Hacker News, its first report on the story. Hackers Exploit Citrix NetScaler Flaws as Forgotten Assets Fuel Attacks. Cites a CVE in CISA KEV.
- Mon 28 Sep, 15:30 UTC. Unit 42, its first report on the story. Citrix NetScaler Zero Days Exploited as 50,000 Systems Exposed. Cites a CVE in CISA KEV.
- Tue 29 Sep, 08:00 UTC. SecurityOnline. Critical NetScaler Flaw Lets Attackers Run Root Commands Unauthenticated. Cites a CVE in CISA KEV.
- Wed 30 Sep, 07:13 UTC. The Hacker News. NetScaler Flaw Exploited to Gain Root Access Before Authentication. Cites a CVE in CISA KEV.
- Wed 30 Sep, 08:25 UTC. Security Affairs. Citrix NetScaler Zero Day Gives Attackers Tunnels Into Internal Networks. Cites a CVE in CISA KEV.
- Wed 30 Sep, 10:13 UTC. The Hacker News. Attackers Exploit Citrix NetScaler Flaw to Deploy Root Web Shells. Cites a CVE in CISA KEV.
- Wed 30 Sep, 13:16 UTC. SecurityWeek. Citrix NetScaler Zero Days Let Attackers Steal Credentials Through Web Shells. Cites a CVE in CISA KEV.
- Thu 1 Oct, 02:14 UTC. SecurityOnline. Active NetScaler Zero Days Expose Devices to Remote Code Execution. Cites a CVE in CISA KEV.
- Thu 1 Oct, 04:38 UTC. The Hacker News. Attackers Exploit Critical NetScaler Flaw to Steal Configurations. Cites a CVE in CISA KEV.
- Thu 1 Oct, 10:28 UTC. SecurityOnline. Citrix NetScaler Zero Day Lets Attackers Seize Root Access Without Passwords. Cites a CVE in CISA KEV.
- Thu 1 Oct, 12:31 UTC. DataBreaches, its first report on the story. Citrix NetScaler Zero Days Exploited Against 50,000 Devices. Cites a CVE in CISA KEV.
- Fri 2 Oct, 17:05 UTC. Dark Reading, its first report on the story. Citrix NetScaler Zero Days Exploited as Vendors Take Different Risks. Cites a CVE in CISA KEV.
- Fri 2 Oct, 22:22 UTC. SecurityOnline. Citrix NetScaler Reboots Persist as SAML Flaw Fix Remains Pending. Cites a CVE in CISA KEV.
- Mon 5 Oct, 05:53 UTC. SecurityWeek. Citrix NetScaler Zero Day Exploited Days After PitScaler Fixes. Cites a CVE in CISA KEV.
- Mon 5 Oct, 13:18 UTC. The Hacker News. Credential sprawl is outpacing security teams’ ability to see it. Cites a CVE in CISA KEV.
- Thu 8 Oct, 18:48 UTC. The Hacker News. ThreatsDay Round-Up Exposes Rogue Affiliates and Leaky Attack Tools. Cites a CVE in CISA KEV.
- Sat 10 Oct, 11:48 UTC. The Hacker News. Enterprise Software’s Hidden AI Agents Create a Security Blind Spot. Cites a CVE in CISA KEV.
- Mon 19 Oct, 13:24 UTC. Cloudflare, its first report on the story. Citrix NetScaler Flaw Sparks Attacks, Prompting Urgent Patching. Cites a CVE in CISA KEV.
- First report
- Article
- Official notice
- Running total
Added to CISA KEV
Show as tableHide table
- Citrix NetScaler Flaw Sparks Attacks, Prompting Urgent PatchingCloudflare · mentions it in passing
- Citrix NetScaler Zero Day Exploited Days After PitScaler FixesSecurityWeek · mentions it in passing
- Citrix NetScaler Reboots Persist as SAML Flaw Fix Remains PendingSecurityOnline · mentions it in passing
- Citrix NetScaler Zero Days Exploited as Vendors Take Different RisksDark Reading · mentions it in passing
- Citrix NetScaler Zero Days Exploited Against 50,000 DevicesDataBreaches · mentions it in passing
- Attackers Exploit Critical NetScaler Flaw to Steal ConfigurationsThe Hacker News · mentions it in passing
- Citrix NetScaler Zero Days Let Attackers Steal Credentials Through Web ShellsSecurityWeek · mentions it in passing
- Critical NetScaler Flaw Lets Attackers Run Root Commands UnauthenticatedSecurityOnline · mentions it in passing
- Citrix NetScaler Zero Days Exploited as 50,000 Systems ExposedUnit 42 · mentions it in passing
- Hackers Exploit Citrix NetScaler Flaws as Forgotten Assets Fuel AttacksThe Hacker News · mentions it in passing
- UK Cyber Agency Urges Action on Exploited Citrix NetScaler FlawsNCSC · official notice · mentions it in passing
- Citrix NetScaler Zero Days Expose Appliances to Active RCE AttacksRapid7 · mentions it in passing
- CISA Warns of Active Exploitation in Critical Citrix NetScaler FlawsSecurity Affairs · mentions it in passing
- Citrix NetScaler Zero Days Exploited in Attacks, Patch NowInfosecurity · mentions it in passing
- Citrix Patches NetScaler Zero Days Exploited in Global AttacksSOCRadar · mentions it in passing
- Citrix Patches NetScaler Zero Days Exploited in Global AttacksSecurityWeek · mentions it in passing
- CISA Warns Attackers Are Exploiting Critical Citrix NetScaler FlawCISA · official notice
- CISA Warns Attackers Are Exploiting Critical Citrix NetScaler Zero-DaysCISA · official notice · mentions it in passing
- CISA Flags Actively Exploited Citrix NetScaler Flaws for Urgent ActionCISA · official notice · mentions it in passing
- Citrix NetScaler Zero Days Exploited Against Unpatched SystemsSecurity Affairs · mentions it in passing
- Citrix NetScaler Zero Days Exploited to Attack VPN AppliancesSecurityOnline · first in our coverage · mentions it in passing
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