How severe is CVE-2021-29261?

CVE-2021-29261 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-29261 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-29261?

CVE-2021-29261 affects Svelte. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-29261?

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-2021-29261 published?

CVE-2021-29261 was published on 2021-04-05 and last updated on 2026-06-17.

CVE-2021-29261

CVE-2021-29261 is a high-severity vulnerability in Svelte with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 6.8
EPSS exploit prediction: 1% (66th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Svelte
Published: 2021-04-05
Last modified: 2026-06-17

Description

The unofficial Svelte extension before 104.8.0 for Visual Studio Code allows attackers to execute arbitrary code via a crafted workspace configuration.

Frequently asked questions

What is CVE-2021-29261?: The unofficial Svelte extension before 104.8.0 for Visual Studio Code allows attackers to execute arbitrary code via a crafted workspace configuration.
How severe is CVE-2021-29261?: CVE-2021-29261 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-29261 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-29261?: CVE-2021-29261 affects Svelte. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-29261?: 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-2021-29261 published?: CVE-2021-29261 was published on 2021-04-05 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:svelte:svelte:*:*:*:*:*:visual_studio_code:*:*

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