November 13, 2026 Follow Egret
CVE-2026-118747 · CVE record: PUBLISHED

.NET Denial of Service Vulnerability

Microsoft System.Formats.Cbor

Inefficient algorithmic complexity in .NET allows an unauthorized attacker to deny service over a network.

Exploitation evidence

Not listed in the latest downloaded CISA KEV catalog. This does not establish an absence of exploitation.

KEV checked 13 Nov 2026, 00:20 Jerusalem · Original catalog ↗

Reported products and versions

Microsoft / System.Formats.Cbor

Default status: Not specified

  • affected: 10.0.0 to < 9.0.24 (custom)

Fixes and workarounds

No explicit solution text in the downloaded CVE record. Consult the vendor advisory; unaffected version ranges are shown above as reported, not inferred as a patch recommendation.

Sources and related reporting

CVE Program record ↗ · Download tracked evidence as JSON

Monitored source mentions

Shared CVE identifiers link source mentions; they do not establish that the reports describe the same incident.

Observed change timeline

History begins when Egret first downloads each source. It is not the complete upstream CVE history.

12 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-12",
  "epss": 0.013,
  "percentile": 0.70851
}
12 Nov 2026, 18:20 Jerusalem · CVE Program record changed

Stored CNA snapshot at this observation.

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11 Nov 2026, 12:20 Jerusalem · CVE Program record changed

Stored CNA snapshot at this observation.

{
  "containers": {
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