How severe is CVE-2021-4263?

CVE-2021-4263 has a CVSS 3.x base score of 3.5, rated low severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2021-4263 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-4263?

CVE-2021-4263 affects Leanote. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-4263?

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

When was CVE-2021-4263 published?

CVE-2021-4263 was published on 2022-12-21 and last updated on 2026-06-17.

CVE-2021-4263

CVE-2021-4263 is a low-severity vulnerability in Leanote with a CVSS 3.x base score of 3.5. 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-79.

Key facts

Severity: Low (CVSS 3.x base score 3.5)
CVSS v2: 4.0
EPSS exploit prediction: 1% (40th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Leanote
Published: 2022-12-21
Last modified: 2026-06-17

Description

A vulnerability, which was classified as problematic, has been found in leanote 2.6.1. This issue affects the function define of the file public/js/plugins/history.js. The manipulation of the argument content leads to cross site scripting. The attack may be initiated remotely. The identifier of the patch is 0f9733c890077942150696dcc6d2b1482b7a0a19. It is recommended to apply a patch to fix this issue. The identifier VDB-216461 was assigned to this vulnerability.

Frequently asked questions

What is CVE-2021-4263?: A vulnerability, which was classified as problematic, has been found in leanote 2.6.1. This issue affects the function define of the file public/js/plugins/history.js. The manipulation of the argument content leads to cross site scripting. The attack may be initiated remotely. The identifier of the patch is 0f9733c890077942150696dcc6d2b1482b7a0a19. It is recommended to apply a patch to fix this issue. The identifier VDB-216461 was assigned to this vulnerability.
How severe is CVE-2021-4263?: CVE-2021-4263 has a CVSS 3.x base score of 3.5, rated low severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2021-4263 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-4263?: CVE-2021-4263 affects Leanote. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-4263?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-4263 published?: CVE-2021-4263 was published on 2022-12-21 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:leanote:leanote:2.6.1:*:*:*:*:*:*:*

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