CVE-2026-42348
📛 CVE Title
OpAMP client reads unbounded HTTP response bodies
Description
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.
Overview
- State
- PUBLISHED
- Assigner (CNA)
- GitHub_M
- CVSS severity
- MEDIUM
- CVSS score
- 5.9 / 10
- CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H- Effective score
- 5.9 / 10 MEDIUM source: CNA overview
- CWE(s)
-
CWE-789 - Reserved
- 2026-04-26
- Published
- 2026-05-12 20:01 UTC
- Last updated
- 2026-05-13 21:32 UTC
- Source
- https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/42xxx/CVE-2026-42348.json
- Linked Threat
- CVE-2026-42348 — CVE-2026-42348
NVD triage scoring NVD CVE 2.0
Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.
- NVD published
- 2026-05-12 18:17:24 UTC
- NVD last modified
- 2026-05-13 18:16:44 UTC
- NVD CVSS v3.1
- 5.9 / 10 MEDIUM source: security-advisories@github.com
- NVD CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H- Exploitability subscore
- 2.2 / 10
- Impact subscore
- 3.6 / 10
- EPSS score
- 0.0002 (probability of exploitation in next 30 days)
- EPSS percentile
- 4.00% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24
NVD / KEV / EPSS data refreshed 2026-05-25 09:31 UTC. Re-run the 🛰 Backfill from NVD button above to refresh.
European Union Vulnerability Database ENISA EUVD
ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.
- EUVD ID
-
EUVD-2026-29706 - Assigner
- GitHub_M
- Published
- May 12, 2026, 6:01:41 PM
- Updated
- May 13, 2026, 7:32:28 PM
- EUVD base score (CVSS 3.1)
-
5.9 / 10
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - EUVD-reported EPSS
- 0.0200
- Vendors
- open-telemetry
- Products
-
opentelemetry-dotnet-contrib (< 0.2.0-alpha.1)
- Aliases
-
GHSA-w2jh-77fq-7gp8
ENISA description: 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.
Affected products (1)
| Vendor | Product | Versions | Platforms |
|---|---|---|---|
| open-telemetry | opentelemetry-dotnet-contrib |
< 0.2.0-alpha.1 (affected)
|
— |
Vendor references (2)
References embedded in the original CVE record by the assigning CNA.
MITRE references (2) cveawg.mitre.org
Pulled from MITRE's CVE Services API by the 🛰 Backfill from MITRE button.
Web references (3)
DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.
- https://nvd.nist.gov/vuln/detail/CVE-2026-42348 tenable:nvd.nist.gov
- https://www.cve.org/CVERecord?id=CVE-2026-42348 tenable:www.cve.org
- https://www.first.org/epss/ tenable:www.first.org
NVD-tagged references (2)
Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.
- https://github.com/open-telemetry/opentelemetry-dotnet-contrib/pull/4116 security-advisories@github.com
- https://github.com/open-telemetry/opentelemetry-dotnet-contrib/security/advisories/GHSA-w2jh-77fq-7gp8 security-advisories@github.com
Remediations (14)
Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.
-
web:cybersecuritynews.com
Microsoft has released its April 2026 Patch Tuesday security update, addressing 168 vulnerabilities across its product portfolio including one actively exploited zero-day and one publicly disclosed flaw that organizations must prioritize immediately.
2026-05-23 20:57 UTC -
web:krebsonsecurity.com
Microsoft expects that exploitation is more likely. May's Patch Tuesday is a welcome respite from April, which saw Microsoft fix a near-record 167 security flaws.
2026-05-23 20:57 UTC -
web:oradba.ch
19c 26ai cve oracle-cpu patch -management release-update security Oracle CPU April 2026 : Delayed RUs & First Analysis On April 21, 2026 , Oracle released the Critical Patch Update (CPU) for April 2026 — 481 new security fixes across the entire Oracle product stack. For Oracle Database, this means another round of mandatory patching.
2026-05-23 20:57 UTC -
web:portal.msrc.microsoft.com
The Security Update Guide provides information on the latest Microsoft security updates, helping users understand and address potential vulnerabilities effectively.
2026-05-23 20:57 UTC -
web:support.servicenow.com
Overview The advisories below document publicly disclosed Common Vulnerabilities and Exposures ( CVEs ) in the Now Platform by ServiceNow. Because ServiceNow uses various methods to communicate vulnerability information, patches, and other fixes, customers should review family, security patch , and hotfix release notes, which are available at https://docs.servicenow.com, for a complete list of ...
2026-05-23 20:57 UTC -
web:www.cisecurity.org
<p>Multiple vulnerabilities have been discovered in Microsoft products, the most severe of which could allow for remote code execution. Successful exploitation of the most severe of these vulnerabilities could result in an attacker gaining the same privileges as the logged-on user. Depending on the privileges associated with the user, an attacker could then install programs; view, change, or ...
2026-05-23 20:57 UTC -
web:www.crowdstrike.com
Microsoft's April 2026 Patch Tuesday addresses 164 CVEs , featuring 8 Critical vulnerabilities, one exploited zero-day, and one disclosed zero-day.
2026-05-23 20:57 UTC -
web:www.oracle.com
This Critical Patch Update contains 481 new security patches across the product families listed below. Please note that an MOS note summarizing the content of this Critical Patch Update and other Oracle Software Security Assurance activities is located at April 2026 Critical Patch Update: Executive Summary and Analysis.
2026-05-23 20:57 UTC -
web:www.windowslatest.com
Windows 11 April 2026 update adds Narrator Copilot support, faster Settings, File Explorer fixes, and key security improvements.
2026-05-23 20:57 UTC -
web:zecurit.com
Get the complete breakdown of Microsoft's May 2026 Patch Tuesday. We analyze the latest security updates and all critical CVEs .
2026-05-23 20:57 UTC -
web:cybersecuritynews.com
Microsoft's May 2026 Patch Tuesday lands with a heavy enterprise focus, fixing 120 vulnerabilities across Windows, Office, Azure, developer tools, and Microsoft 365 apps, including 29 remote code execution (RCE) flaws rated Critical.
2026-06-03 22:32 UTC -
web:thecyberexpress.com
Microsoft has rolled out its May 2026 Patch Tuesday security updates, delivering fixes for approximately 120 vulnerabilities across Windows, Microsoft Office, networking services, and enterprise platforms.
2026-06-03 22:32 UTC -
web:www.bleepingcomputer.com
Today is Microsoft's March 2026 Patch Tuesday with security updates for 79 flaws, including 2 publicly disclosed zero-day vulnerabilities.
2026-06-03 22:32 UTC -
web:www.pdq.com
May 2026 Patch Tuesday is here, and PDQ is back with another recap. Will we see another month of increased CVE volume? Is AI to blame? Dive in to learn more.
2026-06-03 22:32 UTC
AI Forensic Analysis
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Raw JSON
The full cvelistV5 record. Download as CVE-2026-42348.json.
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