How severe is CVE-2021-35440?

CVE-2021-35440 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-35440 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-35440?

CVE-2021-35440 affects Smashing Project Smashing. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-35440?

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

When was CVE-2021-35440 published?

CVE-2021-35440 was published on 2021-07-06 and last updated on 2026-06-17.

CVE-2021-35440

CVE-2021-35440 is a medium-severity vulnerability in Smashing Project Smashing with a CVSS 3.x base score of 6.1. 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 6.1)
CVSS v2: 4.3
EPSS exploit prediction: 1% (58th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Smashing Project Smashing
Published: 2021-07-06
Last modified: 2026-06-17

Description

Smashing 1.3.4 is vulnerable to Cross Site Scripting (XSS). A URL for a widget can be crafted and used to execute JavaScript on the victim's computer. The JavaScript code can then steal data available in the session/cookies depending on the user environment (e.g. if re-using internal URL's for deploying, or cookies that are very permissive) private information may be retrieved by the attacker.

Frequently asked questions

What is CVE-2021-35440?: Smashing 1.3.4 is vulnerable to Cross Site Scripting (XSS). A URL for a widget can be crafted and used to execute JavaScript on the victim's computer. The JavaScript code can then steal data available in the session/cookies depending on the user environment (e.g. if re-using internal URL's for deploying, or cookies that are very permissive) private information may be retrieved by the attacker.
How severe is CVE-2021-35440?: CVE-2021-35440 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-35440 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-35440?: CVE-2021-35440 affects Smashing Project Smashing. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-35440?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-35440 published?: CVE-2021-35440 was published on 2021-07-06 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:smashing_project:smashing:1.3.4:*:*:*:*:*:*:*

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