How severe is CVE-2021-45268?

CVE-2021-45268 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-45268 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-45268?

CVE-2021-45268 affects Backdropcms Backdrop. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-45268?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-45268 published?

CVE-2021-45268 was published on 2022-02-03 and last updated on 2026-06-17.

CVE-2021-45268

CVE-2021-45268 is a high-severity vulnerability in Backdropcms Backdrop with a CVSS 3.x base score of 8.8. 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-352.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.8
EPSS exploit prediction: 2% (76th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-352
Affected product: Backdropcms Backdrop
Published: 2022-02-03
Last modified: 2026-06-17

Description

A Cross Site Request Forgery (CSRF) vulnerability exists in Backdrop CMS 1.20, which allows Remote Attackers to gain Remote Code Execution (RCE) on the Hosting Webserver via uploading a maliciously add-on with crafted PHP file. NOTE: the vendor disputes this because the attack requires a session cookie of a high-privileged authenticated user who is entitled to install arbitrary add-ons

Frequently asked questions

What is CVE-2021-45268?: A Cross Site Request Forgery (CSRF) vulnerability exists in Backdrop CMS 1.20, which allows Remote Attackers to gain Remote Code Execution (RCE) on the Hosting Webserver via uploading a maliciously add-on with crafted PHP file. NOTE: the vendor disputes this because the attack requires a session cookie of a high-privileged authenticated user who is entitled to install arbitrary add-ons
How severe is CVE-2021-45268?: CVE-2021-45268 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-45268 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-45268?: CVE-2021-45268 affects Backdropcms Backdrop. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-45268?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-45268 published?: CVE-2021-45268 was published on 2022-02-03 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:backdropcms:backdrop:1.20.0:*:*:*:*:*:*:*

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