How severe is CVE-2023-36637?

CVE-2023-36637 has a CVSS 3.x base score of 3.5, rated low severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2023-36637 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-36637?

CVE-2023-36637 primarily affects Fortinet Fortimail. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-36637?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-36637 published?

CVE-2023-36637 was published on 2023-10-10 and last updated on 2026-06-17.

CVE-2023-36637

CVE-2023-36637 is a low-severity vulnerability in Fortinet Fortimail with a CVSS 3.x base score of 3.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: Low (CVSS 3.x base score 3.5)
EPSS exploit prediction: 0% (31st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Fortinet Fortimail
Published: 2023-10-10
Last modified: 2026-06-17

Description

An improper neutralization of input during web page generation vulnerability [CWE-79] in FortiMail version 7.2.0 through 7.2.2 and before 7.0.5 allows an authenticated attacker to inject HTML tags in FortiMail's calendar via input fields.

Frequently asked questions

What is CVE-2023-36637?: An improper neutralization of input during web page generation vulnerability [CWE-79] in FortiMail version 7.2.0 through 7.2.2 and before 7.0.5 allows an authenticated attacker to inject HTML tags in FortiMail's calendar via input fields.
How severe is CVE-2023-36637?: CVE-2023-36637 has a CVSS 3.x base score of 3.5, rated low severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2023-36637 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-36637?: CVE-2023-36637 primarily affects Fortinet Fortimail. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-36637?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-36637 published?: CVE-2023-36637 was published on 2023-10-10 and last updated on 2026-06-17.

References

https://fortiguard.com/psirt/FG-IR-23-194

Affected products (4)

cpe:2.3:a:fortinet:fortimail:*:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortimail:7.2.0:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortimail:7.2.1:*:*:*:*:*:*:*
cpe:2.3:a:fortinet:fortimail:7.2.2:*:*:*:*:*:*:*

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