Cyber Resilience

CVE-2026-42348

Opentelemetry.Opamp.Client ≤ 0.2.0

Published
12 May 2026
Modified
17 June 2026
Patch / advisory
CVSS Score v3.1 5.9
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0031 23th percentile
Risk Priority 45 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-42348 is a medium-severity Memory Allocation with Excessive Size Value (CWE-789) vulnerability in Opentelemetry Opentelemetry.Opamp.Client. Its CVSS base score is 5.9 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Endpoint Denial of Service (T1499); ranked at the 23th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SI-10 (Information Input Validation) and SC-6 (Resource Availability) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

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…

more

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.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
T1499.003 Application Exhaustion Flood Impact
Adversaries may target resource intensive features of applications to cause a denial of service (DoS), denying availability to those applications.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-44967Same vendor: Opentelemetry
CVE-2026-41178Same vendor: Opentelemetry
CVE-2026-39882Same vendor: Opentelemetry
CVE-2026-40182Same vendor: Opentelemetry
CVE-2026-40894Same vendor: Opentelemetry
CVE-2026-40891Same vendor: Opentelemetry
CVE-2021-47970Shared CWE-789
CVE-2026-46603Shared CWE-789
CVE-2026-69219Shared CWE-789
CVE-2026-70377Shared CWE-789

Affected Assets

opentelemetry
opentelemetry.opamp.client
≤ 0.2.0

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

Input validation directly rejects or bounds untrusted size values before any allocation occurs.

Resource quotas and priority allocation limit the system-wide impact of an oversized request.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly prevent coding flaws that trust unvalidated size values for allocations.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing in development can detect and block excessive allocation flaws before deployment.

prevents

Secure development lifecycle includes input validation and size checks that prevent unbounded allocations.

prevents

Application security requirements mandate bounds checking on size parameters to avoid excessive memory allocation.

prevents

Secure architecture principles require resource-limit enforcement that mitigates uncontrolled memory requests.

prevents

Secure coding standards directly prohibit allocating memory from untrusted size values without validation.

References