How severe is CVE-2020-8290?

CVE-2020-8290 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-8290 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-8290?

CVE-2020-8290 primarily affects Backblaze. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-8290?

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-2020-8290 published?

CVE-2020-8290 was published on 2020-12-27 and last updated on 2026-06-17.

CVE-2020-8290

CVE-2020-8290 is a high-severity vulnerability in Backblaze with a CVSS 3.x base score of 7.8. 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-269.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 4.6
EPSS exploit prediction: 1% (44th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-269
Affected product: Backblaze
Published: 2020-12-27
Last modified: 2026-06-17

Description

Backblaze for Windows and Backblaze for macOS before 7.0.0.439 suffer from improper privilege management in `bztransmit` helper due to lack of permission handling and validation before creation of client update directories allowing for local escalation of privilege via rogue client update binary.

Frequently asked questions

What is CVE-2020-8290?: Backblaze for Windows and Backblaze for macOS before 7.0.0.439 suffer from improper privilege management in `bztransmit` helper due to lack of permission handling and validation before creation of client update directories allowing for local escalation of privilege via rogue client update binary.
How severe is CVE-2020-8290?: CVE-2020-8290 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-8290 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-8290?: CVE-2020-8290 primarily affects Backblaze. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-8290?: 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-2020-8290 published?: CVE-2020-8290 was published on 2020-12-27 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:backblaze:backblaze:*:*:*:*:*:macos:*:*
cpe:2.3:a:backblaze:backblaze:*:*:*:*:*:windows:*:*

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