How severe is CVE-2021-21255?

CVE-2021-21255 has a CVSS 3.x base score of 5.8, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-21255 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-21255?

CVE-2021-21255 affects Glpi-project Glpi. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-21255?

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

When was CVE-2021-21255 published?

CVE-2021-21255 was published on 2021-03-02 and last updated on 2026-06-17.

CVE-2021-21255

CVE-2021-21255 is a medium-severity vulnerability in Glpi-project Glpi with a CVSS 3.x base score of 5.8. 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-639.

Key facts

Severity: Medium (CVSS 3.x base score 5.8)
CVSS v2: 3.5
EPSS exploit prediction: 1% (54th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-639
Affected product: Glpi-project Glpi
Published: 2021-03-02
Last modified: 2026-06-17

Description

GLPI is an open-source asset and IT management software package that provides ITIL Service Desk features, licenses tracking and software auditing. In GLPI version 9.5.3, it was possible to switch entities with IDOR from a logged in user. This is fixed in version 9.5.4.

Frequently asked questions

What is CVE-2021-21255?: GLPI is an open-source asset and IT management software package that provides ITIL Service Desk features, licenses tracking and software auditing. In GLPI version 9.5.3, it was possible to switch entities with IDOR from a logged in user. This is fixed in version 9.5.4.
How severe is CVE-2021-21255?: CVE-2021-21255 has a CVSS 3.x base score of 5.8, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-21255 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-21255?: CVE-2021-21255 affects Glpi-project Glpi. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-21255?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-21255 published?: CVE-2021-21255 was published on 2021-03-02 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:glpi-project:glpi:9.5.3:*:*:*:*:*:*:*

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