CVE-2026-6993 (GCVE-0-2026-6993)
Vulnerability from cvelistv5 – Published: 2026-04-25 18:30 – Updated: 2026-04-27 13:41 X_Open Source
VLAI
EPSS
VEX
Title
go-kratos http.DefaultServeMux Fallback server.go NewServer confused deputy
Summary
A security flaw has been discovered in go-kratos kratos up to 2.9.2. This impacts the function NewServer of the file transport/http/server.go of the component http.DefaultServeMux Fallback Handler. The manipulation results in unintended intermediary. The attack may be launched remotely. The exploit has been released to the public and may be used for attacks. The patch is identified as 0284a5bcf92b5a7ee015300ce3051baf7ae4718d. Applying a patch is advised to resolve this issue.
Severity
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-27 13:40 UTC
CWE
- CWE-441 - Unintended Intermediary
Assigner
References
7 references
| URL | Tags |
|---|---|
| https://vuldb.com/vuln/359545 | vdb-entrytechnical-description |
| https://vuldb.com/vuln/359545/cti | signaturepermissions-required |
| https://vuldb.com/submit/797099 | third-party-advisory |
| https://github.com/go-kratos/kratos/issues/3810 | exploitissue-tracking |
| https://github.com/go-kratos/kratos/pull/3814 | issue-trackingpatch |
| https://github.com/Yanhu007/kratos/commit/0284a5b… | patch |
| https://github.com/go-kratos/kratos/ | product |
Impacted products
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{
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Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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Vulnerability timeline
Sightings and recorded dates, grouped by day · UTC
How durations are calculated
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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
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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.
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.
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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.