CVE-2020-16904
CVE-2020-16904 is a medium-severity vulnerability in Microsoft Azure Functions with a CVSS 3.x base score of 5.3. 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-863.
Key facts
- Severity: Medium (CVSS 3.x base score 5.3)
- CVSS v2: 7.5
- EPSS exploit prediction: 3% (86th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-863
- Affected product: Microsoft Azure Functions
- Published:
- Last modified:
Description
<p>An elevation of privilege vulnerability exists in the way Azure Functions validate access keys.</p> <p>An unauthenticated attacker who successfully exploited this vulnerability could invoke an HTTP Function without proper authorization.</p> <p>This security update addresses the vulnerability by correctly validating access keys used to access HTTP Functions.</p>
Frequently asked questions
- What is CVE-2020-16904?
- <p>An elevation of privilege vulnerability exists in the way Azure Functions validate access keys.</p> <p>An unauthenticated attacker who successfully exploited this vulnerability could invoke an HTTP Function without proper authorization.</p> <p>This security update addresses the vulnerability by correctly validating access keys used to access HTTP Functions.</p>
- How severe is CVE-2020-16904?
- CVE-2020-16904 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
- Is CVE-2020-16904 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (86th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-16904?
- CVE-2020-16904 affects Microsoft Azure Functions. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2020-16904?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2020-16904 published?
- CVE-2020-16904 was published on 2020-10-16 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:microsoft:azure_functions:-:*:*:*:*:*:*:*
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