ASP.NET Core Information Disclosure Vulnerability
- Exploited
- No known exploitation
- Fix
- Fixed in .NET 10.0 installed on Linux 10.0.15 · .NET 10.0 installed on Mac OS 10.0.15 · .NET 10.0 installed on Windows 10.0.15 · .NET 11.0 installed on Linux 11.0.0 · .NET 11.0 installed on Mac OS 11.0.0 · .NET 11.0 installed on Windows 11.0.0 · .NET 8.0 installed on Linux 8.0.34 · .NET 8.0 installed on Mac OS 8.0.34 · .NET 8.0 installed on Windows 8.0.34 · .NET 9.0 installed on Linux 9.0.23 · .NET 9.0 installed on Mac OS 9.0.23 · .NET 9.0 installed on Windows 9.0.23 · Microsoft Visual Studio 17.14.45, 18.11.4, 18.12.0
- Who is exposed
- Not reported
Do first: Upgrade to a fixed version: .NET 10.0 installed on Linux 10.0.15 · .NET 10.0 installed on Mac OS 10.0.15 · .NET 10.0 installed on Windows 10.0.15 · .NET 11.0 installed on Linux 11.0.0 · .NET 11.0 installed on Mac OS 11.0.0 · .NET 11.0 installed on Windows 11.0.0 · .NET 8.0 installed on Linux 8.0.34 · .NET 8.0 installed on Mac OS 8.0.34 · .NET 8.0 installed on Windows 8.0.34 · .NET 9.0 installed on Linux 9.0.23 · .NET 9.0 installed on Mac OS 9.0.23 · .NET 9.0 installed on Windows 9.0.23 · Microsoft Visual Studio 17.14.45, 18.11.4, 18.12.0.
- Last modified
- Whether it needs action now or is a reference record, by fixed rules, with why. Last checked is when cve.now last re-read it.What do these mean? →
- Reference
- Last checked
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 23/100 · provisional
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: partial
Summary
Improper encoding or escaping of output in ASP.NET Core allows an unauthorized attacker to disclose information over a network.
cve.now Index
- Exploitation0/40No signal
- Exposure7/25Reachable over the network without a login · Unknown: No advisory context yet
- Reach10/20Affects NuGet packages
- Severity6.1/10CVSS 6.1
- No patch0/5No signal
What would change the score
- Would score about 78 if added to CISA KEV
- Would score about 73 if CISA's SSVC rates exploitation active
- Would score about 38 if advisories confirm default setups are exposed
What to do
Upgrade to a fixed version: .NET 10.0 installed on Linux 10.0.15 · .NET 10.0 installed on Mac OS 10.0.15 · .NET 10.0 installed on Windows 10.0.15 · .NET 11.0 installed on Linux 11.0.0 · .NET 11.0 installed on Mac OS 11.0.0 · .NET 11.0 installed on Windows 11.0.0 · .NET 8.0 installed on Linux 8.0.34 · .NET 8.0 installed on Mac OS 8.0.34 · .NET 8.0 installed on Windows 8.0.34 · .NET 9.0 installed on Linux 9.0.23 · .NET 9.0 installed on Mac OS 9.0.23 · .NET 9.0 installed on Windows 9.0.23 · Microsoft Visual Studio 17.14.45, 18.11.4, 18.12.0.
Check your systems with an agent
Paste this into a coding or ops agent. It checks your systems read-only and reports a table per asset.
Check whether my systems are affected by CVE-2026-109476 (ASP.NET Core Information Disclosure Vulnerability), using the cve.now data below. Rules: work read-only. Do not run exploit code, proof-of-concept scripts or scanners that send attack payloads, and do not change any configuration, package, image or deployment. Report findings only. What cve.now has for CVE-2026-109476 (entry last updated 2026-11-10): Affected: - Microsoft .NET 10.0 installed on Linux: from 10.0.0, fixed in 10.0.15 - Microsoft .NET 10.0 installed on Mac OS: from 10.0.0, fixed in 10.0.15 - Microsoft .NET 10.0 installed on Windows: from 10.0.0, fixed in 10.0.15 - Microsoft .NET 11.0 installed on Linux: from 11.0.0-preview.1, fixed in 11.0.0 - Microsoft .NET 11.0 installed on Mac OS: from 11.0.0-preview.1, fixed in 11.0.0 - Microsoft .NET 11.0 installed on Windows: from 11.0.0-preview.1, fixed in 11.0.0 - Microsoft .NET 8.0 installed on Linux: from 8.0.0, fixed in 8.0.34 - Microsoft .NET 8.0 installed on Mac OS: from 8.0.0, fixed in 8.0.34 - Microsoft .NET 8.0 installed on Windows: from 8.0.0, fixed in 8.0.34 - Microsoft .NET 9.0 installed on Linux: from 9.0.0, fixed in 9.0.23 - and 49 more affected products, listed on https://cve.now/CVE-2026-109476 Fixed versions: 10.0.15, 11.0.0, 8.0.34, 9.0.23, 17.14.45, 18.11.4, 18.12.0. Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory. CISA KEV: CVE-2026-109476 is not listed as of cve.now's last read. This KEV status is for CVE-2026-109476 only. If you also check another CVE, look up its own KEV status; never assume it from this one. How to check: - Packages (NuGet): find every lockfile in each project and run check_stack from the cve.now MCP server on each one. Compare the resolved versions, not the ranges a manifest declares, with the affected versions above. Include transitive dependencies. - Installed software: check what is actually running, not what a repo declares. Read the version from each host, container image and Kubernetes node (the binary's version output, the OS package database, image layers), and check whether the conditions above hold there. Distribution packages may carry a backported fix under an older version number; confirm against the distribution's own advisory. Verify against the linked advisories before concluding, and cite the date you read each one: - https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-109476 Do not conclude an asset is unaffected unless you checked it and the evidence covers both its version and the conditions above. If you could not check something, mark it unknown and say what is missing. Report a table with one row per asset and these columns: Asset | Version or build | Status (affected, fixed, not applicable, unknown) | Compensating controls | Exposure (internet-facing, internal, none) | Evidence | Next action. Entry: https://cve.now/CVE-2026-109476 For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example get_vulnerability with id CVE-2026-109476.
Timeline
- CVE published
- First seen by cve.now
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: partial
- Record last updated
Affected versions
- Microsoft .NET 10.0 installed on Linux
From 10.0.0 · fixed in 10.0.15
- Microsoft .NET 10.0 installed on Mac OS
From 10.0.0 · fixed in 10.0.15
- Microsoft .NET 10.0 installed on Windows
From 10.0.0 · fixed in 10.0.15
- Microsoft .NET 11.0 installed on Linux
From 11.0.0-preview.1 · fixed in 11.0.0
- Microsoft .NET 11.0 installed on Mac OS
From 11.0.0-preview.1 · fixed in 11.0.0
- Microsoft .NET 11.0 installed on Windows
From 11.0.0-preview.1 · fixed in 11.0.0
- Microsoft .NET 8.0 installed on Linux
From 8.0.0 · fixed in 8.0.34
- Microsoft .NET 8.0 installed on Mac OS
From 8.0.0 · fixed in 8.0.34
Show all 59 packagesShow fewer packages
- Microsoft .NET 8.0 installed on Windows
From 8.0.0 · fixed in 8.0.34
- Microsoft .NET 9.0 installed on Linux
From 9.0.0 · fixed in 9.0.23
- Microsoft .NET 9.0 installed on Mac OS
From 9.0.0 · fixed in 9.0.23
- Microsoft .NET 9.0 installed on Windows
From 9.0.0 · fixed in 9.0.23
- Microsoft Microsoft Visual Studio 2022 version 17.14
From 17.14.0 · fixed in 17.14.45
- Microsoft Microsoft Visual Studio 2026 version 18.11
From 18.11.0 · fixed in 18.11.4
- Microsoft Microsoft Visual Studio 2026 version 18.12
From 18.12.0 · fixed in 18.12.0
From 8.0.0-rc.1.23421.29 · fixed in 8.0.34
No fix released. The advisory names 8.0.34 and 9.0.23 and 10.0.15 and 11.0.0 as the fix, which the registry doesn't have yet. The latest release, 10.0.14, is still affected.
From 8.0.0-rc.1.23421.29 · fixed in 8.0.34
No fix released. The advisory names 8.0.34 and 9.0.23 and 10.0.15 and 11.0.0 as the fix, which the registry doesn't have yet. The latest release, 10.0.14, is still affected.
From 8.0.0-rc.1.23421.29 · fixed in 8.0.34
No fix released. The advisory names 8.0.34 and 9.0.23 and 10.0.15 and 11.0.0 as the fix, which the registry doesn't have yet. The latest release, 10.0.14, is still affected.
From 8.0.0-rc.1.23421.29 · fixed in 8.0.34
No fix released. The advisory names 8.0.34 and 9.0.23 and 10.0.15 and 11.0.0 as the fix, which the registry doesn't have yet. The latest release, 10.0.14, is still affected.
From 8.0.0-rc.1.23421.29 · fixed in 8.0.34
No fix released. The advisory names 8.0.34 and 9.0.23 and 10.0.15 and 11.0.0 as the fix, which the registry doesn't have yet. The latest release, 10.0.14, is still affected.
From 8.0.0-rc.1.23421.29 · fixed in 8.0.34
From 8.0.0-rc.1.23421.29 · fixed in 8.0.34
From 8.0.0-rc.1.23421.29 · fixed in 8.0.34
From 8.0.0-rc.1.23421.29 · fixed in 8.0.34
From 8.0.0-rc.1.23421.29 · fixed in 8.0.34
From 8.0.0-rc.1.23421.29 · fixed in 8.0.34
From 9.0.0-preview.1.24081.5 · fixed in 9.0.23
From 9.0.0-preview.1.24081.5 · fixed in 9.0.23
From 9.0.0-preview.1.24081.5 · fixed in 9.0.23
From 9.0.0-preview.1.24081.5 · fixed in 9.0.23
From 9.0.0-preview.1.24081.5 · fixed in 9.0.23
From 9.0.0-preview.1.24081.5 · fixed in 9.0.23
From 9.0.0-preview.1.24081.5 · fixed in 9.0.23
From 9.0.0-preview.1.24081.5 · fixed in 9.0.23
From 9.0.0-preview.1.24081.5 · fixed in 9.0.23
From 9.0.0-preview.1.24081.5 · fixed in 9.0.23
From 9.0.0-preview.1.24081.5 · fixed in 9.0.23
From 10.0.0-preview.1.25120.3 · fixed in 10.0.15
From 10.0.0-preview.1.25120.3 · fixed in 10.0.15
From 10.0.0-preview.1.25120.3 · fixed in 10.0.15
From 10.0.0-preview.1.25120.3 · fixed in 10.0.15
From 10.0.0-preview.1.25120.3 · fixed in 10.0.15
From 10.0.0-preview.1.25120.3 · fixed in 10.0.15
From 10.0.0-preview.1.25120.3 · fixed in 10.0.15
From 10.0.0-preview.1.25120.3 · fixed in 10.0.15
From 10.0.0-preview.1.25120.3 · fixed in 10.0.15
From 10.0.0-preview.1.25120.3 · fixed in 10.0.15
From 10.0.0-preview.1.25120.3 · fixed in 10.0.15
From 11.0.0-preview.1.26104.118 · fixed in 11.0.0
From 11.0.0-preview.1.26104.118 · fixed in 11.0.0
From 11.0.0-preview.1.26104.118 · fixed in 11.0.0
From 11.0.0-preview.1.26104.118 · fixed in 11.0.0
From 11.0.0-preview.1.26104.118 · fixed in 11.0.0
From 11.0.0-preview.1.26104.118 · fixed in 11.0.0
From 11.0.0-preview.1.26104.118 · fixed in 11.0.0
From 11.0.0-preview.1.26104.118 · fixed in 11.0.0
From 11.0.0-preview.1.26104.118 · fixed in 11.0.0
From 11.0.0-preview.1.26104.118 · fixed in 11.0.0
From 11.0.0-preview.1.26104.118 · fixed in 11.0.0
Evidence 3
Vendor advisory · 1
Establishes: Affected and fixed versions.
- Patch
CVE record · 2
Establishes: The identifier and description.
- Record
- Record
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-109476
Is CVE-2026-109476 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
Which versions are affected by CVE-2026-109476?
.NET 10.0 installed on Linux: from 10.0.0 before 10.0.15. .NET 10.0 installed on Mac OS: from 10.0.0 before 10.0.15. .NET 10.0 installed on Windows: from 10.0.0 before 10.0.15. .NET 11.0 installed on Linux: from 11.0.0-preview.1 before 11.0.0. .NET 11.0 installed on Mac OS: from 11.0.0-preview.1 before 11.0.0. 54 more packages are listed on the page.Source: cve.now feed data
How do I fix CVE-2026-109476?
Upgrade to a fixed version: .NET 10.0 installed on Linux 10.0.15 · .NET 10.0 installed on Mac OS 10.0.15 · .NET 10.0 installed on Windows 10.0.15 · .NET 11.0 installed on Linux 11.0.0 · .NET 11.0 installed on Mac OS 11.0.0 · .NET 11.0 installed on Windows 11.0.0 · .NET 8.0 installed on Linux 8.0.34 · .NET 8.0 installed on Mac OS 8.0.34 · .NET 8.0 installed on Windows 8.0.34 · .NET 9.0 installed on Linux 9.0.23 · .NET 9.0 installed on Mac OS 9.0.23 · .NET 9.0 installed on Windows 9.0.23 · Microsoft Visual Studio 17.14.45, 18.11.4, 18.12.0.Source: cve.now feed data