How severe is CVE-2023-27997?

CVE-2023-27997 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-27997 being actively exploited?

Yes. CVE-2023-27997 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2023-06-13, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2023-27997?

CVE-2023-27997 primarily affects Fortinet Fortiproxy. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-27997?

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-2023-27997 have an EU (EUVD) identifier?

Yes. CVE-2023-27997 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-31722. It is also flagged as exploited in the EUVD (since 2023-06-13).

When was CVE-2023-27997 published?

CVE-2023-27997 was published on 2023-06-13 and last updated on 2026-07-31.

CVE-2023-27997

CVE-2023-27997 is a critical-severity vulnerability in Fortinet Fortiproxy with a CVSS 3.x base score of 9.8. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2023-06-13). The underlying weakness is classified as CWE-787.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
EPSS exploit prediction: 86% (100th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2023-06-13)
EU (EUVD) id: EUVD-2023-31722
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2023-06-13)
Weakness: CWE-787
Affected product: Fortinet Fortiproxy
Published: 2023-06-13
Last modified: 2026-07-31

Description

A heap-based buffer overflow vulnerability [CWE-122] in FortiOS version 7.2.4 and below, version 7.0.11 and below, version 6.4.12 and below, version 6.0.16 and below and FortiProxy version 7.2.3 and below, version 7.0.9 and below, version 2.0.12 and below, version 1.2 all versions, version 1.1 all versions SSL-VPN may allow a remote attacker to execute arbitrary code or commands via specifically crafted requests.

Frequently asked questions

What is CVE-2023-27997?: A heap-based buffer overflow vulnerability [CWE-122] in FortiOS version 7.2.4 and below, version 7.0.11 and below, version 6.4.12 and below, version 6.0.16 and below and FortiProxy version 7.2.3 and below, version 7.0.9 and below, version 2.0.12 and below, version 1.2 all versions, version 1.1 all versions SSL-VPN may allow a remote attacker to execute arbitrary code or commands via specifically crafted requests.
How severe is CVE-2023-27997?: CVE-2023-27997 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-27997 being actively exploited?: Yes. CVE-2023-27997 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2023-06-13, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2023-27997?: CVE-2023-27997 primarily affects Fortinet Fortiproxy. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-27997?: 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-2023-27997 have an EU (EUVD) identifier?: Yes. CVE-2023-27997 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-31722. It is also flagged as exploited in the EUVD (since 2023-06-13).
When was CVE-2023-27997 published?: CVE-2023-27997 was published on 2023-06-13 and last updated on 2026-07-31.

References

Affected products (13)

cpe:2.3:a:fortinet:fortiproxy:*:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:*:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:6.0.10:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:6.2.4:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:6.2.6:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:6.2.7:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:6.4.2:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:6.4.6:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:6.4.8:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:6.4.10:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:6.4.12:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:7.0.5:*:*:*:*:*:*:*
cpe:2.3:o:fortinet:fortios:7.0.10:*:*:*:*:*:*:*

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