{"id":"CVE-2026-42348","aliases":["GHSA-w2jh-77fq-7gp8"],"url":"https://o3.security/vulnerability/CVE-2026-42348","summary":"OpAMP client reads unbounded HTTP response bodies","details":"OpenTelemetry.OpAmp.Client is the OpAMP client for OpenTelemetry .NET. Prior to 0.2.0-alpha.1, when receiving responses from the OpAMP server over HTTP, the OpAMP client allocates an unbounded buffer to read all bytes from the server, with no upper-bound on the number of bytes consumed. This could cause memory exhaustion in the consuming application if the configured OpAMP server is attacker-controlled (or a network attacker can MitM the connection) and an extremely large body is returned in the response. This vulnerability is fixed in 0.2.0-alpha.1.","published":"2026-05-12T18:01:41.812Z","modified":"2026-08-07T11:31:31.053630980Z","cvss":{"score":5.9,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"},"epss":{"score":0.00311,"percentile":0.23506,"asOf":"2026-08-08"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"NuGet","name":"OpenTelemetry.OpAmp.Client","fixedVersion":"0.2.0-alpha.1"}],"fix":{"url":"https://github.com/open-telemetry/opentelemetry-dotnet-contrib/pull/4116","label":"open-telemetry/opentelemetry-dotnet-contrib#4116"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/42xxx/CVE-2026-42348.json"},{"type":"ADVISORY","url":"https://github.com/open-telemetry/opentelemetry-dotnet-contrib/security/advisories/GHSA-w2jh-77fq-7gp8"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-42348"},{"type":"FIX","url":"https://github.com/open-telemetry/opentelemetry-dotnet-contrib/pull/4116"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-07T11:31:31.053630980Z"}}