How severe is CVE-2021-3818?

CVE-2021-3818 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2021-3818 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3818?

CVE-2021-3818 affects Getgrav Grav. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-3818?

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

When was CVE-2021-3818 published?

CVE-2021-3818 was published on 2021-09-27 and last updated on 2026-06-17.

CVE-2021-3818

CVE-2021-3818 is a medium-severity vulnerability in Getgrav Grav with a CVSS 3.x base score of 5.3. 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-565.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 2% (82nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-565
Affected product: Getgrav Grav
Published: 2021-09-27
Last modified: 2026-06-17

Description

grav is vulnerable to Reliance on Cookies without Validation and Integrity Checking

Frequently asked questions

What is CVE-2021-3818?: grav is vulnerable to Reliance on Cookies without Validation and Integrity Checking
How severe is CVE-2021-3818?: CVE-2021-3818 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2021-3818 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3818?: CVE-2021-3818 affects Getgrav Grav. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-3818?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-3818 published?: CVE-2021-3818 was published on 2021-09-27 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:getgrav:grav:*:*:*:*:*:*:*:*

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