Vulnerability-Lookup

OPENSUSE-SU-2026:21771-1

Vulnerability from csaf_opensuse - Published: 2026-09-06 16:48 - Updated: 2026-09-17 17:43

Summary

Security update for mcphost

Severity

Moderate

Notes

Title of the patch: Security update for mcphost

Description of the patch: This update for mcphost fixes the following issues: - CVE-2026-41178: go.opentelemetry.io/otel/baggage: no rejection of raw-length headers in baggage parsing allows for DoS via oversized inputs (bsc#1276612). - CVE-2026-81092: github.com/mark3labs/mcp-go/server: requests accepted in HTTP transports without Host header checks can lead to tool usage and resource exposure in target server (bsc#1278013). Changes for mcphost: - Update github.com/mark3labs/mcp-go/server to v0.56.0. - Update go.opentelemetry.io/otel to 1.44.0.

Patchnames: openSUSE-Leap-16.0-1619

CVE-2026-41178

5.3 (Medium)


                
                  CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Affected products

Recommended 7 products

Product	Version	Remediation
Unresolved product id: openSUSE Leap 16.0:mcphost-0:0.34.0-160000.4.1.aarch64	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:mcphost-0:0.34.0-160000.4.1.ppc64le	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:mcphost-0:0.34.0-160000.4.1.s390x	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:mcphost-0:0.34.0-160000.4.1.x86_64	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:mcphost-bash-completion-0:0.34.0-160000.4.1.noarch	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:mcphost-fish-completion-0:0.34.0-160000.4.1.noarch	—	Vendor Fix
Unresolved product id: openSUSE Leap 16.0:mcphost-zsh-completion-0:0.34.0-160000.4.1.noarch	—	Vendor Fix

Threats

Impact moderate

CVE-2026-81092

6.8 (Medium)


                
                  CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N

Affected products

Recommended 7 products, the same list as for CVE-2026-41178

Threats

Impact moderate

References

10 references

URL	Category
https://www.suse.com/support/security/rating/	external
https://ftp.suse.com/pub/projects/security/csaf/o…	self
https://bugzilla.suse.com/1276612	self
https://bugzilla.suse.com/1278013	self
https://www.suse.com/security/cve/CVE-2026-41178/	self
https://www.suse.com/security/cve/CVE-2026-81092/	self
https://www.suse.com/security/cve/CVE-2026-41178	external
https://bugzilla.suse.com/1276509	external
https://www.suse.com/security/cve/CVE-2026-81092	external
https://bugzilla.suse.com/1278012	external

JSON

To clipboard

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        }
      ],
      "threats": [
        {
          "category": "impact",
          "date": "2026-09-06T16:48:02Z",
          "details": "moderate"
        }
      ],
      "title": "CVE-2026-81092"
    }
  ]
}

CVE-2026-41178 (GCVE-0-2026-41178)

Vulnerability from cvelistv5 – Published: 2026-06-04 14:38 – Updated: 2026-06-04 15:46

Title

OpenTelemetry-Go's baggage parsing no longer caps raw header length

Summary

OpenTelemetry-Go is the Go implementation of OpenTelemetry. Versions 1.41.0 and 1.43.0 removed raw-length rejection and it causes `Parse` to process arbitrarily large/invalid baggage headers and log errors, enabling DoS via oversized inputs. Versions 1.42.0 and 1.44.0 fix the issue.

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

SSVC

Exploitation: poc Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-06-04 15:46 UTC

CWE

CWE-789 - Memory Allocation with Excessive Size Value

Assigner

GitHub_M mitre root

References

2 references

URL	Tags
https://github.com/open-telemetry/opentelemetry-g…	x_refsource_CONFIRM
https://github.com/open-telemetry/opentelemetry-g…	x_refsource_MISC

Impacted products

2 products

Vendor	Product	Version
open-telemetry	go.opentelemetry.io/otel/baggage	Affected: = 1.41.0 Affected: = 1.43.0
open-telemetry	go.opentelemetry.io/otel/propagation	Affected: = 1.41.0 Affected: = 1.43.0

Show details on NVD website

JSON

To clipboard

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CVE-2026-81092 (GCVE-0-2026-81092)

Vulnerability from cvelistv5 – Published: 2026-08-27 14:50 – Updated: 2026-08-29 11:48

Title

mcp-go before 0.56.0 Missing Host Header Validation Enables DNS Rebinding

Summary

mcp-go accepted requests on its HTTP transports without checking the Host header. StreamableHTTPServer.ServeHTTP in server/streamable_http.go and SSEServer.ServeHTTP in server/sse.go served any request arriving over a loopback connection regardless of the host it named, and the SSE transport's cross-origin default allowed any origin. A page in a browser could therefore point a name it controlled at the loopback address and reach a server listening there, invoking tools and reading resources that the server exposed on the assumption that only local software could connect. No release before 0.56.0 validated the header on either transport; 0.56.0 adds server/http_localhost.go, which rejects a loopback-bound request carrying a host that is not a loopback name, and wires it into both transports.

Severity

7.6 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

6.8 (Medium)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-27 18:24 UTC

CWE

CWE-346 - Origin Validation Error

Assigner

VulnCheck mitre root

References

4 references

URL	Tags
https://github.com/mark3labs/mcp-go	product
https://github.com/mark3labs/mcp-go/pull/921	issue-trackingpatch
https://github.com/mark3labs/mcp-go/releases/tag/…	release-notes
https://www.vulncheck.com/advisories/mcp-go-befor…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
mark3labs	mcp-go	Affected: 0 , < 0.56.0 (semver)

Date Public

2026-08-26 00:00

Credits

Avishai Gonen (Pluto Security)

Show details on NVD website

JSON

To clipboard

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

OPENSUSE-SU-2026:21771-1

CVE-2026-41178 (GCVE-0-2026-41178)

CVE-2026-81092 (GCVE-0-2026-81092)

Tags

Sightings

Nomenclature

Related by attack behaviour