Networks
CVE-2026-88777
Memory overflow in Citrix NetScaler ADC/Gateway enabling remote DoS
Major vulnerability. Citrix NetScaler ADC/Gateway are widely deployed enterprise network appliances; a DoS against these perimeter devices can disrupt access and services across organizations.
- CVSS
- 8.8Highscored by the publisher (CNA)
- Exploited in the wild
- Not knownUnvetted proof-of-concept code on GitHub; not in CISA KEV
- EPSS
- 0.72%chance of exploitation in the next 30 daystop 46% of scored CVEsFIRST score of 11 Nov 2026
- Fix
- Patch availablesee the advisories in the references
- Published
- 27 Sept 2026analysed here 28 Sept 2026
Summary
Impact
Remote memory overflow can crash or cause unpredictable behavior in NetScaler ADC/Gateway, resulting in denial of service to applications and users.
The summary, impact and action text on this page are written by our AI analysis pipeline, or taken from the NVD description when a CVE was imported from NVD. They are not the vendor's wording: check them against the sources. A longer AI executive summary and technical analysis are generated for signed-in accounts on the Max plan.
Affected products
| Product | Affected versions | Vendor says fixed in |
|---|---|---|
| Citrix NetScaler ADC | < 14.1-73.37< 13.1-64.23< 14.1-73.37 FIPS< 13.1.37.279 FIPS and NDcPPVendor says fixed in: not stated | |
| Citrix NetScaler Gateway | < 14.1-73.37< 13.1-64.23Vendor says fixed in: not stated |
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.
Products named in our analysis
- Citrix NetScaler ADC < 14.1-73.37
- Citrix NetScaler ADC < 13.1-64.23
- ADC FIPS < 14.1-73.37 FIPS
- ADC FIPS < 13.1.37.279 FIPS and NDcPP
- Citrix NetScaler Gateway < 14.1-73.37
- Citrix NetScaler Gateway < 13.1-64.23
Fix and mitigation
Action required
Immediate action required
Remediation steps (AI-written)
Step-by-step remediation is generated for accounts on the Max plan, for CVEs that match a technology in their stack. Add this technology to your stack to see the fix checklist.
Exploitation evidence
- CISA KEV catalog
- Not listed as of our last sync.
- Public exploit code
- Unvetted proof-of-concept code on GitHub: 1 GitHub proof of concept
- CISA SSVC
- exploitation none, automatable yes, technical impact partialAssessed by CISA 29 Sept 2026 (SSVC 2.0.3). Exploitation is none, poc (public proof of concept) or active.
GitHub proofs of concept
Listed so you can judge urgency, not as a recommendation to run anything. GitHub “proofs of concept” are unvetted: some are fake or carry malware. Exploit-DB marks the entries its staff verified.
Timeline
- 27 Sept 2026Published
- 28 Sept 2026Analysed by vulneraibility.com1 day later
- 29 Sept 2026CISA SSVC assessment: exploitation none1 day later
- 29 Sept 2026CVE record last updatedsame day later
- 23 Oct 2026First proof-of-concept repository on GitHub (unvetted)23 days later
Common questions
Is CVE-2026-88777 being exploited?
Not confirmed. CVE-2026-88777 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.72% probability of exploitation in the next 30 days.
How severe is CVE-2026-88777?
CVE-2026-88777 is rated High with a CVSS score of 8.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-88777?
Yes. A fix has been recorded for CVE-2026-88777. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-88777 affect?
CVE-2026-88777 affects Citrix NetScaler ADC < 14.1-73.37, Citrix NetScaler ADC < 13.1-64.23, ADC FIPS < 14.1-73.37 FIPS, ADC FIPS < 13.1.37.279 FIPS and NDcPP, and 2 further products or versions. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-88777?
Apply Citrix updates to 14.1-73.37 / 13.1-64.23 or later immediately
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
References
1 reference in the CVE record, grouped by the tags the record gives them.
Other links (1)
- support.citrix.com /support-home/kbsearch/article?articleNumber=CTX697096&articleTitle=Citrix_NetSc
Where the data on this page comes from
- CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
- NVD: CVSS and CPE data
- CISA Vulnrichment (ADP): SSVC decision points
- FIRST EPSS: exploit probability and percentile
- PoC-in-GitHub: GitHub repositories that claim a proof of concept
Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.
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