How severe is CVE-2019-12991?

CVE-2019-12991 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2019-12991 being actively exploited?

Yes. CVE-2019-12991 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-03-25, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2019-12991?

CVE-2019-12991 primarily affects Citrix Netscaler Sd-wan. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-12991?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2019-12991 have an EU (EUVD) identifier?

Yes. CVE-2019-12991 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2019-4566. It is also flagged as exploited in the EUVD (since 2022-03-25).

When was CVE-2019-12991 published?

CVE-2019-12991 was published on 2019-07-16 and last updated on 2026-06-17.

CVE-2019-12991

CVE-2019-12991 is a high-severity vulnerability in Citrix Netscaler Sd-wan with a CVSS 3.x base score of 8.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2022-03-25). The underlying weakness is classified as CWE-78.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 9.0
EPSS exploit prediction: 74% (99th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2022-03-25)
EU (EUVD) id: EUVD-2019-4566
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2022-03-25)
Weakness: CWE-78
Affected product: Citrix Netscaler Sd-wan
Published: 2019-07-16
Last modified: 2026-06-17

Description

Citrix SD-WAN 10.2.x before 10.2.3 and NetScaler SD-WAN 10.0.x before 10.0.8 have Improper Input Validation (issue 5 of 6).

Frequently asked questions

What is CVE-2019-12991?: Citrix SD-WAN 10.2.x before 10.2.3 and NetScaler SD-WAN 10.0.x before 10.0.8 have Improper Input Validation (issue 5 of 6).
How severe is CVE-2019-12991?: CVE-2019-12991 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2019-12991 being actively exploited?: Yes. CVE-2019-12991 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-03-25, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2019-12991?: CVE-2019-12991 primarily affects Citrix Netscaler Sd-wan. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-12991?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2019-12991 have an EU (EUVD) identifier?: Yes. CVE-2019-12991 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2019-4566. It is also flagged as exploited in the EUVD (since 2022-03-25).
When was CVE-2019-12991 published?: CVE-2019-12991 was published on 2019-07-16 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:citrix:netscaler_sd-wan:*:*:*:*:*:*:*:*
cpe:2.3:a:citrix:sd-wan:*:*:*:*:*:*:*:*

More vulnerabilities in Citrix Netscaler Sd-wan

CVE-2019-12990 — Critical (CVSS 9.8): Citrix SD-WAN 10.2.x before 10.2.3 and NetScaler SD-WAN 10.0.x before 10.0.8 allow Directory Traversal.
CVE-2019-12989 — Critical (CVSS 9.8): Citrix SD-WAN 10.2.x before 10.2.3 and NetScaler SD-WAN 10.0.x before 10.0.8 allow SQL Injection.
CVE-2019-12988 — Critical (CVSS 9.8): Citrix SD-WAN 10.2.x before 10.2.3 and NetScaler SD-WAN 10.0.x before 10.0.8 have Improper Input Validation (issue 4 of…
CVE-2019-12987 — Critical (CVSS 9.8): Citrix SD-WAN 10.2.x before 10.2.3 and NetScaler SD-WAN 10.0.x before 10.0.8 have Improper Input Validation (issue 3 of…
CVE-2019-12986 — Critical (CVSS 9.8): Citrix SD-WAN 10.2.x before 10.2.3 and NetScaler SD-WAN 10.0.x before 10.0.8 have Improper Input Validation (issue 2 of…
CVE-2019-12985 — Critical (CVSS 9.8): Citrix SD-WAN 10.2.x before 10.2.3 and NetScaler SD-WAN 10.0.x before 10.0.8 have Improper Input Validation (issue 1 of…

All CVEs affecting Citrix Netscaler Sd-wan →

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