How severe is CVE-2025-55315?

CVE-2025-55315 has a CVSS 3.x base score of 9.9, rated critical 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 low.

Is CVE-2025-55315 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 66% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-55315?

CVE-2025-55315 primarily affects Microsoft Asp.net Core. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2025-55315?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2025-55315 have an EU (EUVD) identifier?

Yes. CVE-2025-55315 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-34426.

When was CVE-2025-55315 published?

CVE-2025-55315 was published on 2025-10-14 and last updated on 2026-06-17.

CVE-2025-55315

CVE-2025-55315 is a critical-severity vulnerability in Microsoft Asp.net Core with a CVSS 3.x base score of 9.9. Its EPSS exploit-prediction score of 66% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-444.

Key facts

Severity: Critical (CVSS 3.x base score 9.9)
EPSS exploit prediction: 66% (99th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-34426
Weakness: CWE-444
Affected product: Microsoft Asp.net Core
Published: 2025-10-14
Last modified: 2026-06-17

Description

Inconsistent interpretation of http requests ('http request/response smuggling') in ASP.NET Core allows an authorized attacker to bypass a security feature over a network.

Frequently asked questions

What is CVE-2025-55315?: Inconsistent interpretation of http requests ('http request/response smuggling') in ASP.NET Core allows an authorized attacker to bypass a security feature over a network.
How severe is CVE-2025-55315?: CVE-2025-55315 has a CVSS 3.x base score of 9.9, rated critical 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 low.
Is CVE-2025-55315 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 66% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-55315?: CVE-2025-55315 primarily affects Microsoft Asp.net Core. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2025-55315?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2025-55315 have an EU (EUVD) identifier?: Yes. CVE-2025-55315 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-34426.
When was CVE-2025-55315 published?: CVE-2025-55315 was published on 2025-10-14 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:microsoft:asp.net_core:*:*:*:*:*:*:*:*
cpe:2.3:a:microsoft:visual_studio_2022:*:*:*:*:*:*:*:*

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