How severe is CVE-2026-50659?

CVE-2026-50659 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2026-50659 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-2026-50659?

CVE-2026-50659 primarily affects Microsoft .net Framework. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-50659?

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

When was CVE-2026-50659 published?

CVE-2026-50659 was published on 2026-07-14 and last updated on 2026-07-24.

CVE-2026-50659

CVE-2026-50659 is a medium-severity vulnerability in Microsoft .net Framework with a CVSS 3.x base score of 6.5. 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-116.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
EPSS exploit prediction: 1% (44th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-116
Affected product: Microsoft .net Framework
Published: 2026-07-14
Last modified: 2026-07-24

Description

Improper encoding or escaping of output in .NET allows an authorized attacker to perform spoofing over a network.

Frequently asked questions

What is CVE-2026-50659?: Improper encoding or escaping of output in .NET allows an authorized attacker to perform spoofing over a network.
How severe is CVE-2026-50659?: CVE-2026-50659 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2026-50659 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-2026-50659?: CVE-2026-50659 primarily affects Microsoft .net Framework. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-50659?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-50659 published?: CVE-2026-50659 was published on 2026-07-14 and last updated on 2026-07-24.

References

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-50659

Affected products (10)

cpe:2.3:a:microsoft:.net_framework:4.8.1:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:.net_framework:4.8:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:.net_framework:4.6.2:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:.net_framework:4.7:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:.net_framework:4.7.1:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:.net_framework:4.7.2:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:.net:*:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:.net_framework:3.5:-:*:*:*:*:*:*
cpe:2.3:a:microsoft:visual_studio_2022:*:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:visual_studio_2026:*:*:*:*:*:*:*:*

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