CVE-2026-3055Insufficient input validation leading to memory overread
- 9.3CriticalCVSS base score
- 91.5%Exploitation in 30 daysEPSS · top 0.2% of all CVEs
- YesKnown exploitedin CISA's KEV since 30 Mar 2026
- 2Public exploitsMetasploit, Nuclei and Exploit-DB
Description
Insufficient input validation in NetScaler ADC and NetScaler Gateway when configured as a SAML IDP leading to memory overread
Exploited in the wild
CISA lists this vulnerability in its Known Exploited Vulnerabilities catalog as Citrix NetScaler Out-of-Bounds Read Vulnerability.
- Added
- 30 Mar 2026
- Fix due (US federal)
- 2 Apr 2026
- Used by ransomware
- Not known
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
ENISA's EU Vulnerability Database lists it as exploited, from CISA's KEV, since 30 Mar 2026.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. The public collections list a Metasploit module and a Nuclei template for it. CISA's SSVC rates its exploitation: it is being exploited.
Show the exploits2
Metasploit modules1 module
- Citrix ADC (NetScaler) CVE-2026-3055 Scanner (Metasploit module) (opens in a new tab)
auxiliary/scanner/http/citrix_netscaler_cve_2026_3055Rank normaldisclosed 23 Mar 2026
Nuclei templates1 template
- Citrix NetScaler SAML IDP - Memory Overread (Nuclei template) (opens in a new tab)
http/cves/2026/CVE-2026-3055.yamlSeverity critical
Modules, templates and exploits as listed by the Metasploit Framework (BSD-3-Clause), ProjectDiscovery's Nuclei templates (MIT) and the Exploit Database (GPLv2), read once a day. Where the data comes from
Timeline
ID reserved
By NetScaler
- 28 days later
· 28 days later
Published
- 7 days later
· 7 days later
Added to CISA KEV
Known exploited in the wild
- 1 day later
· 1 day later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| NetScalerCNA (assigner) | 4.0 | Critical9.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L |
| NVDNVD · Analyzed | 4.0 | Critical9.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 91.5% · top 0.2% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: active · Automatable: yes · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.3.
Affected products
References
References3
- https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX696300 (opens in a new tab)
- https://labs.watchtowr.com/please-we-beg-just-one-weekend-free-of-appliances-citrix-netscaler-cve-2026-3055-memory-overread-part-2/ (opens in a new tab)third-party-advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-3055 (opens in a new tab)government-resource
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- CISA KEV catalog (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-14546 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-3055)Record last updated .