How severe is CVE-2018-1000813?

CVE-2018-1000813 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2018-1000813 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-1000813?

CVE-2018-1000813 affects Backdropcms Backdrop Cms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-1000813?

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

When was CVE-2018-1000813 published?

CVE-2018-1000813 was published on 2018-12-20 and last updated on 2026-06-17.

CVE-2018-1000813

CVE-2018-1000813 is a medium-severity vulnerability in Backdropcms Backdrop Cms with a CVSS 3.x base score of 4.8. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 4.8)
CVSS v2: 3.5
EPSS exploit prediction: 1% (50th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Backdropcms Backdrop Cms
Published: 2018-12-20
Last modified: 2026-06-17

Description

Backdrop CMS version 1.11.0 and earlier contains a Cross Site Scripting (XSS) vulnerability in Sanitization of custom class names used on blocks and layouts. that can result in Execution of JavaScript from an unexpected source.. This attack appear to be exploitable via A user must be directed to an affected page while logged in.. This vulnerability appears to have been fixed in 1.11.1 and later.

Frequently asked questions

What is CVE-2018-1000813?: Backdrop CMS version 1.11.0 and earlier contains a Cross Site Scripting (XSS) vulnerability in Sanitization of custom class names used on blocks and layouts. that can result in Execution of JavaScript from an unexpected source.. This attack appear to be exploitable via A user must be directed to an affected page while logged in.. This vulnerability appears to have been fixed in 1.11.1 and later.
How severe is CVE-2018-1000813?: CVE-2018-1000813 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2018-1000813 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-1000813?: CVE-2018-1000813 affects Backdropcms Backdrop Cms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-1000813?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-1000813 published?: CVE-2018-1000813 was published on 2018-12-20 and last updated on 2026-06-17.

References

https://backdropcms.org/security/backdrop-sa-core-2018-005

Affected products (1)

cpe:2.3:a:backdropcms:backdrop_cms:*:*:*:*:*:*:*:*

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