goshs has ACL Bypass & Path Traversal

CISA KEV is observed exploitation evidence. FIRST EPSS is a dated prediction of exploitation in the next 30 days. Missing scores are unknown. This collector requests predictions only for explicit CVE aliases in the public NuGet archive; Microsoft release views retain their existing prediction scope.

No collected risk observation for these identifiers. This does not establish absence of exploitation or a zero probability.

goshs is a feature-rich single-binary file server for red teamers and developers. Prior to 2.1.5, the httpserver/handler.go sendFile handler opened files using a cleaned path but derived the authorization filename from raw req.URL.Path, so a trailing slash could bypass .goshs ACL-file protection and block-list checks. This issue is fixed in version 2.1.5.

Source published

28 Jul 2026 22:12:04 UTC

Source modified

29 Jul 2026 15:24:11 UTC

Observed here

23 Oct 2026 15:48:27 UTC

Source terms

CVE Program Terms of Use

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: cve-program · CVE Program Terms of Use. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

goshs is a feature-rich single-binary file server for red teamers and developers. Prior to 2.1.5, the httpserver/handler.go sendFile handler opened files using a cleaned path but derived the authorization filename from raw req.URL.Path, so a trailing slash could bypass .goshs ACL-file protection and block-list checks. This issue is fixed in version 2.1.5.

Source published

28 Jul 2026 23:17:10 UTC

Source modified

23 Oct 2026 23:10:00 UTC

Observed here

25 Oct 2026 15:18:51 UTC

Source terms

NIST NVD usage terms; underlying source attribution retained

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: nvd · NIST NVD usage terms; underlying source attribution retained. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS 3.1 · [email protected] · Secondary · 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

## Summary `sendFile` derives the served filename from the raw request path while opening the file from the cleaned path, so appending a trailing slash empties the derived name and defeats both the never-serve rule for the ACL file and the block list. ## Finding (Medium): trailing-slash ACL and hidden-file bypass httpserver/handler.go, sendFile (lines 789-801) takes the filename from the RAW req.URL.Path while the file itself is opened from the filepath.Clean-ed path. The two disagree, and a trailing slash makes the derived name the empty string. Both protections key on that derived name, so both are defeated: the rule that never serves the .goshs ACL file, and the acl.Block list. Measured, with negative controls: ``` GET /blocked/secret.txt -> 404 (control, correctly blocked) GET /blocked/secret.txt/ -> 200 + contents GET /blocked/.goshs/ -> 200, returns the ACL file itself, including the admin:$2a$... bcrypt hash ``` Unauthenticated when the ACL is configured block-only (common usage). Stated precisely: AUTHENTICATION IS NOT BYPASSED. An unauthenticated request against a directory protected by authentication still returns 401 under the same trick; I tested that. The claim is specifically that the block list and the ACL-file protection are bypassed. In-tree evidence that sendFile is the defect: the sibling handlers doDir and bulkDownload both derive the name correctly; sendFile is the lone outlier. ## Suggested fixes 1. Derive the served filename from the same cleaned path used to open the file, so the authorization decision and the file access cannot disagree. ## Tooling AI assistance was used while investigating. The finding was reproduced against a running server on loopback with negative controls, including the 404-versus-200 pair and the authenticated-directory control that shows authentication is not affected.

Source published

28 Jul 2026 22:26:28 UTC

Source modified

18 Aug 2026 15:10:57 UTC

Observed here

24 Oct 2026 13:19:41 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V3 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Publisher rating · MODERATE

goshs has ACL Bypass & Path Traversal in github.com/patrickhener/goshs

Source published

18 Aug 2026 14:32:29 UTC

Source modified

18 Aug 2026 15:00:21 UTC

Observed here

24 Oct 2026 13:19:41 UTC

Source terms

OSV · upstream source license applies

Original source record · Cite this exact observation · Complete original publisher JSON

This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · OSV · upstream source license applies. Source text is retained; field grouping and change labels are provided by ChangeIntel.