How severe is CVE-2018-21030?

CVE-2018-21030 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-2018-21030 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-21030?

CVE-2018-21030 affects Jupyter Notebook. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-21030?

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

When was CVE-2018-21030 published?

CVE-2018-21030 was published on 2019-10-31 and last updated on 2026-06-17.

CVE-2018-21030

CVE-2018-21030 is a medium-severity vulnerability in Jupyter Notebook 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (70th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Jupyter Notebook
Published: 2019-10-31
Last modified: 2026-06-17

Description

Jupyter Notebook before 5.5.0 does not use a CSP header to treat served files as belonging to a separate origin. Thus, for example, an XSS payload can be placed in an SVG document.

Frequently asked questions

What is CVE-2018-21030?: Jupyter Notebook before 5.5.0 does not use a CSP header to treat served files as belonging to a separate origin. Thus, for example, an XSS payload can be placed in an SVG document.
How severe is CVE-2018-21030?: CVE-2018-21030 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-2018-21030 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-21030?: CVE-2018-21030 affects Jupyter Notebook. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-21030?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-21030 published?: CVE-2018-21030 was published on 2019-10-31 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:jupyter:notebook:*:*:*:*:*:*:*:*

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