CVE-2026-64863: goshs --no-delete WebDAV MOVE bypass allows file deletion/overwrite

Should you act?

Critical and remotely reachable

No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• Not in CISA KEV, but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
• EPSS 0.6%, percentile 49: FIRST’s model estimates a 0.6% chance of exploitation activity in the next 30 days, higher than 49% of all scored CVEs (low). EPSS is a probability, not a verdict.
• Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
• Only applies if your dependency tree includes goshs.de/goshs/v2 (Go) <= 2.1.3, fixed in 2.1.4; github.com/patrickhener/goshs/v2 (Go) <= 2.1.3, fixed in 2.1.4; goshs.de/goshs (Go) <= 1.1.4, no fixed version listed; github.com/patrickhener/goshs (Go) <= 1.1.4, no fixed version listed. Check your lockfile, including transitive dependencies.

What it is

goshs is a feature-rich single-binary file server for red teamers and developers. Prior to 2.1.4, the httpserver/server.go wdGuard handled WebDAV MOVE as a write-only method and did not enforce --no-delete, allowing WebDAV clients to delete or overwrite files via MOVE with Overwrite: T. This issue is fixed in version 2.1.4.

From the GitHub advisory

Summary

The WebDAV mode-flag guard added to fix GHSA-3whc-qvhv-xqjp still does not enforce --no-delete on the WebDAV MOVE verb. MOVE deletes the source file (rename removes it from its original path), and with Overwrite: T it additionally performs an explicit RemoveAll on the destination. Under -w --no-delete, DELETE is correctly blocked (403) but MOVE still destroys existing files, defeating the documented "Disable the delete option" boundary.

This is a residual of the parent fix: the guard classifies MOVE/COPY as write-only verbs (blocked only under --read-only) and never treats MOVE as a delete, so the --no-delete branch never covers it.

Affected

goshs v2.1.3 (current release, commit ba00ce3). The guard was introduced when GHSA-3whc-qvhv-xqjp was fixed and carries the gap forward.

Weakness type: CWE-284.

Product: goshs.de/goshs/v2 (Go) · Assigned by: GitHub_M · Published: 2026-07-28

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: none (no login)
• User interaction: none
• Scope: unchanged

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation poc, automatable yes, technical impact partial.
• FIRST EPSS (model of 2026-10-21): 0.63% probability of exploitation activity in the next 30 days; percentile 49.

Timeline

• 2026-07-28 — CVE record published by GitHub_M
• 2026-07-28 — GitHub-reviewed advisory GHSA-hq33-8jgp-8qq3 published (critical)
• 2026-07-29 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-hq33-8jgp-8qq3 github.com
2. CVE.org record CVE-2026-64863 cve.org
3. NVD entry CVE-2026-64863 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com
2. github.com github.com
3. github.com github.com

Critical Go advisories · Today’s Security Digest