CVE-2026-47300
CVE-2026-47300 is a high-severity vulnerability in Microsoft .net 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-303.
Key facts
- Severity: High (CVSS 3.x base score 8.8)
- EPSS exploit prediction: 1% (54th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-303
- Affected product: Microsoft .net
- Published:
- Last modified:
Description
Incorrect implementation of authentication algorithm in ASP.NET Core allows an authorized attacker to elevate privileges over a network.
Frequently asked questions
- What is CVE-2026-47300?
- Incorrect implementation of authentication algorithm in ASP.NET Core allows an authorized attacker to elevate privileges over a network.
- How severe is CVE-2026-47300?
- CVE-2026-47300 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-2026-47300 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-2026-47300?
- CVE-2026-47300 primarily affects Microsoft .net. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2026-47300?
- 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-2026-47300 published?
- CVE-2026-47300 was published on 2026-07-14 and last updated on 2026-07-22.
References
Affected products (3)
- cpe:2.3:a:microsoft:.net:*:*:*:*:*:*:*:*
- cpe:2.3:a:microsoft:visual_studio_2022:*:*:*:*:*:*:*:*
- cpe:2.3:a:microsoft:visual_studio_2026:*:*:*:*:*:*:*:*
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