How severe is CVE-2022-40276?

CVE-2022-40276 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2022-40276 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-40276?

CVE-2022-40276 affects Zettlr. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2022-40276?

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

When was CVE-2022-40276 published?

CVE-2022-40276 was published on 2022-11-03 and last updated on 2026-06-17.

CVE-2022-40276

CVE-2022-40276 is a medium-severity vulnerability in Zettlr with a CVSS 3.x base score of 5.5. 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 5.5)
EPSS exploit prediction: 0% (29th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Zettlr
Published: 2022-11-03
Last modified: 2026-06-17

Description

Zettlr version 2.3.0 allows an external attacker to remotely obtain arbitrary local files on any client that attempts to view a malicious markdown file through Zettlr. This is possible because the application does not have a CSP policy (or at least not strict enough) and/or does not properly validate the contents of markdown files before rendering them.

Frequently asked questions

What is CVE-2022-40276?: Zettlr version 2.3.0 allows an external attacker to remotely obtain arbitrary local files on any client that attempts to view a malicious markdown file through Zettlr. This is possible because the application does not have a CSP policy (or at least not strict enough) and/or does not properly validate the contents of markdown files before rendering them.
How severe is CVE-2022-40276?: CVE-2022-40276 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2022-40276 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-40276?: CVE-2022-40276 affects Zettlr. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2022-40276?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2022-40276 published?: CVE-2022-40276 was published on 2022-11-03 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:zettlr:zettlr:2.3.0:*:*:*:*:*:*:*

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