CVE-2026-43982 (GCVE-0-2026-43982)
Vulnerability from cvelistv5 – Published: 2026-05-26 16:30 – Updated: 2026-05-26 17:20
VLAI
EPSS
VEX
Title
Algernon: Path traversal file write via savein()
Summary
Algernon is a small self-contained pure-Go web server. Prior to 1.17.6, uploadedFileSaveIn() in lua/upload/upload.go uses filepath.Join() with the caller-supplied directory but performs no boundary check after joining. A directory of ../../../tmp resolves cleanly to /tmp, outside the web root. This vulnerability is fixed in 1.17.6.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-26 17:17 UTC
CWE
- CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/xyproto/algernon/security/advi… | x_refsource_CONFIRM |
| https://github.com/xyproto/algernon/issues/172 | x_refsource_MISC |
Impacted products
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"lastModified": "2026-07-24T11:10:00.170",
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Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
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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
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.
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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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