CVSS 3.1
7.5 highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HCVE-2026-118747 .NET Denial of Service Vulnerability
High (7.5) in microsoft system.formats.cbor. EPSS 1.3% estimated probability of exploitation activity in the next 30 days. Fixed in System.Formats.Cbor 10.0.15, 11.0.0, 8.0.2.
On this page
Inefficient algorithmic complexity in .NET allows an unauthorized attacker to deny service over a network.
Severity
- EPSS
- 1.3% estimated probability of exploitation activity in the next 30 days; 71st percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: yes · Technical impact: partial, assessed 2026-11-10. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-407 Inefficient Algorithmic Complexity
- Published
- Modified
- Assigned by
- microsoft (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| Microsoft System.Formats.Cbor | from 10.0.0 before 9.0.24 |
Fix and patched versions
System.Formats.Cbor(NuGet): fixed in 8.0.2, 9.0.24, 10.0.15, 11.0.0- Alpine: fixed package versions per release
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-vmv3-wvjp-wqpj | NuGet | System.Formats.Cbor | >=8.0.0-0 <8.0.2 | 8.0.2 |
| GHSA-vmv3-wvjp-wqpj | NuGet | System.Formats.Cbor | >=9.0.0-0 <9.0.24 | 9.0.24 |
| GHSA-vmv3-wvjp-wqpj | NuGet | System.Formats.Cbor | >=10.0.0-0 <10.0.15 | 10.0.15 |
| GHSA-vmv3-wvjp-wqpj | NuGet | System.Formats.Cbor | >=11.0.0-0 <11.0.0 | 11.0.0 |
Linux distributions
| Distribution | Release | Package | Fixed in | Advisory |
|---|---|---|---|---|
| Ubuntu | 22.04:LTS | dotnet7 | no fix listed | UBUNTU-CVE-2026-118747 |
| Alpine | v3.22, v3.23, v3.24 | dotnet8-runtime | 8.0.34-r0 | ALPINE-CVE-2026-118747 |
| Alpine | v3.24 | dotnet10-runtime | 10.0.15-r0 | ALPINE-CVE-2026-118747 |
From the distributions' data via OSV.dev: Ubuntu Security Notices © Canonical Ltd., CC BY-SA 4.0; the Alpine secdb, CC BY-SA 4.0. Modified: reformatted and linked to CVE records. Credits. On the distributions' own pages: Ubuntu · Alpine.