How severe is CVE-2021-33895?

CVE-2021-33895 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-33895 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33895?

CVE-2021-33895 primarily affects Hpe Backbox H4.09 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-33895?

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-2021-33895 published?

CVE-2021-33895 was published on 2021-06-25 and last updated on 2026-06-17.

CVE-2021-33895

CVE-2021-33895 is a high-severity vulnerability in Hpe Backbox H4.09 Firmware with a CVSS 3.x base score of 8.1. 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-287.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 6.8
EPSS exploit prediction: 1% (55th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Hpe Backbox H4.09 Firmware
Published: 2021-06-25
Last modified: 2026-06-17

Description

ETINET BACKBOX E4.09 and H4.09 mismanages password access control. When a user uses the User ID of the process running BBSV to login to the Backbox UI application, the system procedure (USER_AUTHENTICATE_) used for verifying the Password returns 0 (no error). The reason is that the user is not running the XYGate application. Hence, BBSV assumes the Password is correct. For H4.09, the affected version isT0954V04^AAO. For E4.09, the affected version is 22SEP2020. Note: If your current version is E4.10-16MAY2021 (version procedure T9999V04_16MAY2022_BPAKETI_10), a hotfix (FIXPAK-19OCT-2022) is available in version E4.10-19OCT2022. Resolution to CVE-2021-33895 in version E4.11-19OCT2022

Frequently asked questions

What is CVE-2021-33895?: ETINET BACKBOX E4.09 and H4.09 mismanages password access control. When a user uses the User ID of the process running BBSV to login to the Backbox UI application, the system procedure (USER_AUTHENTICATE_) used for verifying the Password returns 0 (no error). The reason is that the user is not running the XYGate application. Hence, BBSV assumes the Password is correct. For H4.09, the affected version isT0954V04^AAO. For E4.09, the affected version is 22SEP2020. Note: If your current version is E4.10-16MAY2021 (version procedure T9999V04_16MAY2022_BPAKETI_10), a hotfix (FIXPAK-19OCT-2022) is available in version E4.10-19OCT2022. Resolution to CVE-2021-33895 in version E4.11-19OCT2022
How severe is CVE-2021-33895?: CVE-2021-33895 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-33895 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (55th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33895?: CVE-2021-33895 primarily affects Hpe Backbox H4.09 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-33895?: 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-2021-33895 published?: CVE-2021-33895 was published on 2021-06-25 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:o:hpe:backbox_h4.09_firmware:t0954v04\^aao:*:*:*:*:*:*:*
cpe:2.3:o:etinet:backbox_e4.09_firmware:2020-09-22:*:*:*:*:*:*:*

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