How severe is CVE-2020-26138?

CVE-2020-26138 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-2020-26138 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-26138?

CVE-2020-26138 primarily affects Silverstripe. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-26138?

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

When was CVE-2020-26138 published?

CVE-2020-26138 was published on 2021-06-08 and last updated on 2026-06-17.

CVE-2020-26138

CVE-2020-26138 is a medium-severity vulnerability in Silverstripe 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (68th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Silverstripe
Published: 2021-06-08
Last modified: 2026-06-17

Description

In SilverStripe through 4.6.0-rc1, a FormField with square brackets in the field name skips validation.

Frequently asked questions

What is CVE-2020-26138?: In SilverStripe through 4.6.0-rc1, a FormField with square brackets in the field name skips validation.
How severe is CVE-2020-26138?: CVE-2020-26138 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-2020-26138 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-26138?: CVE-2020-26138 primarily affects Silverstripe. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-26138?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-26138 published?: CVE-2020-26138 was published on 2021-06-08 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:silverstripe:silverstripe:*:*:*:*:*:*:*:*
cpe:2.3:a:silverstripe:silverstripe:4.6.0:rc1:*:*:*:*:*:*

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