CVE-2026-40372

Publication date 21 April 2026

Last updated 24 April 2026

Ubuntu priority

Why this priority?

Cvss 3 Severity Score

Score breakdown

Description

Improper verification of cryptographic signature in ASP.NET Core allows an unauthorized attacker to elevate privileges over a network.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
dotnet6	25.10 questing	Not in release
	24.04 LTS noble	Not in release
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not in release
	18.04 LTS bionic	Not in release
	16.04 LTS xenial	Not in release
	14.04 LTS trusty	Not in release
dotnet7	25.10 questing	Not in release
	24.04 LTS noble	Not in release
	22.04 LTS jammy	Ignored see notes
	20.04 LTS focal	Not in release
	18.04 LTS bionic	Not in release
	16.04 LTS xenial	Not in release
	14.04 LTS trusty	Not in release
dotnet8	25.10 questing	Not affected
	24.04 LTS noble	Not affected
	22.04 LTS jammy	Not affected
	20.04 LTS focal	Not in release
	18.04 LTS bionic	Not in release
	16.04 LTS xenial	Not in release
	14.04 LTS trusty	Not in release
dotnet9	25.10 questing	Not affected
	24.04 LTS noble	Not in release
	22.04 LTS jammy	Not in release
	20.04 LTS focal	Not in release
	18.04 LTS bionic	Not in release
	16.04 LTS xenial	Not in release
	14.04 LTS trusty	Not in release
dotnet10	25.10 questing	Vulnerable
	24.04 LTS noble	Vulnerable
	22.04 LTS jammy	Not in release
	20.04 LTS focal	Not in release
	18.04 LTS bionic	Not in release
	16.04 LTS xenial	Not in release
	14.04 LTS trusty	Not in release

Notes

iconstantin

.NET 7 is end of life upstream.

Severity score breakdown

Parameter	Value
Base score	9.1 · Critical
Attack vector	Network
Attack complexity	Low
Privileges required	None
User interaction	None
Scope	Unchanged
Confidentiality	High
Integrity impact	High
Availability impact	None
Vector	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

References

Other references

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