CVE-2025-5777
7.5, high Known exploited Used in ransomwareCitrix NetScaler ADC and Gateway Out-of-Bounds Read Vulnerability
- CVSS
- 7.5, high high CVSS v3.1
- EPSS, next 30 days
- 100% higher than 99.9% of scored CVEs
- Exploitation
- Confirmed in the wild
- Published
- 17 Jun 2025a year ago
Known exploited
CISA added this to the Known Exploited Vulnerabilities Catalog on 10 Jul 2025 and links it to ransomware activity. US federal agencies had to remediate by 11 Jul 2025, a deadline that has passed.
Required action. Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Description
Insufficient input validation leading to memory overread when the NetScaler is configured as a Gateway (VPN virtual server, ICA Proxy, CVPN, RDP Proxy) OR AAA virtual server
Details
- Vendor
- Citrix
- Product
- ADC
- Weakness
- CWE-125 (opens in a new tab)
- Status
- Analyzed
- Updated
- 8 Oct 2026
- Assigner
- secure@citrix.com
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
References 10
Patches and fixes 1
Advisories 7
- citrixbleed.com (opens in a new tab)
- doublepulsar.com /citrixbleed-2-exploitation-started-mid-june-how-to-spot-it-f3106392aa71 (opens in a new tab)
- horizon3.ai /attack-research/attack-blogs/cve-2025-5777-citrixbleed-2-write-up-maybe/ (opens in a new tab)
- labs.watchtowr.com /how-much-more-must-we-bleed-citrix-netscaler-memory-disclosure-citrixbleed-2-cve-2025-5777/ (opens in a new tab)
- reliaquest.com /blog/threat-spotlight-citrix-bleed-2-vulnerability-in-netscaler-adc-gateway-devices/ (opens in a new tab)
- support.citrix.com /support-home/kbsearch/article?articleNumber=CTX693420 (opens in a new tab)
- netscaler.com /blog/news/netscaler-critical-security-updates-for-cve-2025-6543-and-cve-2025-5777/ (opens in a new tab)
The kind is read from NVD's tags where present and from the shape of the URL otherwise, so treat it as a hint.
Other Citrix CVEs
Every Citrix CVE we holdSame vendor in what we hold, not a known link between the flaws.
- CVE-2026-88779 Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability KEV EPSS 0.6% 7.5, high
- CVE-2026-88771 Citrix NetScaler Improper Input Validation Vulnerability KEV EPSS 1% 9.8, critical
- CVE-2026-88772 Citrix NetScaler Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability KEV EPSS 1% 8.1, high
- CVE-2026-19490 Citrix NetScaler Authentication Bypass Using an Alternate Path or Channel Vulnerability KEV EPSS 23% 9.8, critical
- CVE-2026-8452 Citrix NetScaler ADC and NetScaler Gateway Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability KEV EPSS 1% 9.8, critical
- CVE-2026-3055 Citrix NetScaler Out-of-Bounds Read Vulnerability KEV EPSS 4% 9.8, critical
- CVE-2025-7775 Citrix NetScaler Memory Overflow Vulnerability KEV EPSS 20% 9.8, critical
- CVE-2025-6543 Citrix NetScaler ADC and Gateway Buffer Overflow Vulnerability KEV EPSS 11% 9.8, critical
Beyond this page
Is CVE-2025-5777 in your network?
This page tells you how dangerous CVE-2025-5777 is out there. Whether it sits on one of your devices, only a scan of your own network can tell. That is what our systems do, every day, for the companies we protect.
CVE-2025-5777 is in the CISA catalogue of exploited vulnerabilities: attackers are already exploiting it.
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EXYS7600 OCELOT
Find it before attackers do
Ocelot scans your network on a schedule and reports every vulnerability it finds by its CVE identifier, with its CVSS score and how many of your hosts are affected. A finding like CVE-2025-5777 comes with the devices to patch.
Learn more about EXYS7600 OCELOT -
EXYS7950 KONDRA
Detect it if it's exploited
Until the patch is applied, Kondra monitors your network, events and endpoints in real time. It keeps an inventory of the software installed on every endpoint, and its anomaly detection rules flag what an attacker does once inside.
Learn more about EXYS7950 KONDRA
Assembled from the NVD 2.0 API, the CISA Known Exploited Vulnerabilities Catalog and FIRST EPSS. Scores are as of our last collection on 17 Oct 2026, not the live upstream state.