Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
The OpenTelemetry.OpAmp.Client NuGet package is affected in versions before 0.2.0-alpha.1. An attacker who controls the configured OpAMP server, or who can intercept the connection, can return an extremely large HTTP response body that the client reads without any size limit, exhausting the application's memory. Upgrade to 0.2.0-alpha.1 or later, which limits HTTP response sizes to 128KB; no workaround is listed.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 5.9 | Medium | 3.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.0031, the 24th percentile, on 9 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 15:22 UTC First seen by agentprime
- 31 Oct 2026, 15:22 UTC Confirmed by OSV
Sources
- GitHub Advisory Database: GHSA-w2jh-77fq-7gp8
- OSV: GHSA-w2jh-77fq-7gp8
- github.com/open-telemetry/opentelemetry-dotnet-contrib/security/advisories/GHSA-w2jh-77fq-7gp8
- nvd.nist.gov/vuln/detail/CVE-2026-42348
- github.com/open-telemetry/opentelemetry-dotnet-contrib/pull/4116
- github.com/open-telemetry/opentelemetry-dotnet-contrib/commit/bf1fad4fa298ff451cda0efb0ee9c7a7eb46212a
- github.com/open-telemetry/opentelemetry-dotnet-contrib