How severe is CVE-2021-27522?

CVE-2021-27522 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-27522 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-27522?

CVE-2021-27522 affects Learnsite Project Learnsite. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-27522?

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-2021-27522 published?

CVE-2021-27522 was published on 2021-04-08 and last updated on 2026-06-17.

CVE-2021-27522

CVE-2021-27522 is a high-severity vulnerability in Learnsite Project Learnsite with a CVSS 3.x base score of 8.8. 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-287.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 1% (62nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Learnsite Project Learnsite
Published: 2021-04-08
Last modified: 2026-06-17

Description

Learnsite 1.2.5.0 contains a remote privilege escalation vulnerability in /Manager/index.aspx through the JudgIsAdmin() function. By modifying the initial letter of the key of a user cookie, the key of the administrator cookie can be obtained.

Frequently asked questions

What is CVE-2021-27522?: Learnsite 1.2.5.0 contains a remote privilege escalation vulnerability in /Manager/index.aspx through the JudgIsAdmin() function. By modifying the initial letter of the key of a user cookie, the key of the administrator cookie can be obtained.
How severe is CVE-2021-27522?: CVE-2021-27522 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-27522 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27522?: CVE-2021-27522 affects Learnsite Project Learnsite. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-27522?: 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-2021-27522 published?: CVE-2021-27522 was published on 2021-04-08 and last updated on 2026-06-17.

References

https://github.com/WaterCountry/Learnsite/issues/1

Affected products (1)

cpe:2.3:a:learnsite_project:learnsite:1.2.5.0:*:*:*:*:*:*:*

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