# CVE-2026-3055: NetScaler - Memory Disclosure

> Live exploitation tracking for CVE-2026-3055 by the CrowdSec Live Exploit Tracker, built from real-world attack data crowdsourced from CrowdSec's global network.

Page: https://tracker.crowdsec.net/cves/CVE-2026-3055

## Key facts

- **Exploitation phase:** Limited Exploitation. The vulnerability is known but shows very limited attacker interest or exploitation activity.
- **CVSS score:** 9.3
- **Public exploit available:** Yes
- **Affected products:** Citrix NetScaler ADC, Citrix NetScaler Gateway
- **Weaknesses:** CWE-125 (Out-of-bounds Read)
- **Tags:** sslvpn

## Description

Insufficient input validation leading to memory overread in NetScaler ADC and NetScaler Gateway when configured as a SAML Identity Provider (SAML IDP).

## CrowdSec analysis

[CVE-2026-3055](https://euvd.enisa.europa.eu/vulnerability/CVE-2026-3055) is a critical memory overread vulnerability in Citrix NetScaler ADC and NetScaler Gateway when configured as a SAML Identity Provider. Due to insufficient input validation, unauthenticated attackers can trigger an out-of-bounds read that leaks sensitive memory contents, including administrative session cookies, potentially enabling full appliance compromise.

CrowdSec has been tracking this vulnerability and its exploits since 30th of March 2026.

CrowdSec network data shows that most actors exploiting CVE-2026-3055 rely on broad, untargeted scans with minimal filtering. The activity is largely automated and opportunistic in nature.
Additionally, according to week-over-week analysis by CrowdSec, exploitation of CVE-2026-3055 is surging. Attack volumes are spiking well above historical norms, indicating widespread and escalating interest from threat actors. CVE-2026-3055 is currently experiencing high visibility and active exploitation across the internet.

Attackers exploit the SAML IDP endpoints by sending crafted POST requests to `/saml/login` with a malicious SAMLRequest payload, or GET requests to `/wsfed/passive?wctx` with an empty parameter value, triggering memory overread that leaks sensitive data such as session cookies in the `NSC_TASS` cookie.

## Timeline

- 2026-03-23: CVE Published. CVE-2026-3055 is published to NVD.
- 2026-03-30: Rule Released. CrowdSec releases a rule to detect CVE-2026-3055 exploitation attempts against the CrowdSec Network.
- 2026-03-30: CrowdSec First Seen. CrowdSec observes in-the-wild exploitation of CVE-2026-3055 for the first time.
- 2026-03-30: CISA KEV. CVE-2026-3055 is added to the Known Exploited Vulnerabilities catalog by CISA.
- 2026-04-02: CISA Remediation Deadline. Expiration of the CISA remediation deadline as described in [BOD 22-01](https://www.cisa.gov/news-events/directives/bod-22-01-reducing-significant-risk-known-exploited-vulnerabilities).

## References

- https://support.citrix.com/support-home/kbsearch/article?articleNumber=CTX696300
- https://labs.watchtowr.com/the-sequels-are-never-as-good-but-were-still-in-pain-citrix-netscaler-cve-2026-3055-memory-overread/
- https://labs.watchtowr.com/please-we-beg-just-one-weekend-free-of-appliances-citrix-netscaler-cve-2026-3055-memory-overread-part-2/
- https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-3055.yaml

## Live exploitation data

The [Live Exploit Tracker page](https://tracker.crowdsec.net/cves/CVE-2026-3055) follows observed exploitation activity for CVE-2026-3055. [Request an API key](https://tracker.crowdsec.net/request-api-key) for full access to its exploitation timeline, attacking IP addresses and blocklists.