SFTPGo: Denial of service via malformed SSH channel request

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

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

EPSS

• CVE-2026-77375: 0.31% estimated exploitation activity in the next 30 days; percentile 23.75 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary A flaw in the SSH service allows an authenticated client to crash the server by sending a malformed protocol message while opening a channel. Impact Any user able to authenticate over SSH can trigger an unhandled error condition that aborts the server process. This results in a denial of service affecting all connected users until the service is restarted. No confidentiality or integrity impact has been identified; the issue is limited to availability.

Published by the source

15 Oct 2026, 20:14 UTC

Last modified by the source

19 Oct 2026, 21:31 UTC

Source last checked

26 Oct 2026, 15:32 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-q7pc-356p-hggc

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GO-2026-6792

3. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-q7pc-356p-hggc

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# Patch Next advisory brief: CVE-2026-77375

Advisory: SFTPGo: Denial of service via malformed SSH channel request
IDs: CVE-2026-77375, GHSA-q7pc-356p-hggc
Record: https://patchnext.com/advisories/cve-2026-77375 (revision 3, source checked 26 Oct 2026, 15:32 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Partial vendor fix; fixed versions by package: github.com/drakkan/sftpgo/v2 2.7.5. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/drakkan/sftpgo/v2: affected <= 2.7.4; fixed in 2.7.5
- Go github.com/drakkan/sftpgo: affected every version

## Suggested inspection (read-only)
- Go github.com/drakkan/sftpgo/v2: check the installed version with your package manager.
- Go github.com/drakkan/sftpgo: check the installed version with your package manager.

## Supported action
No complete vendor fix is recorded. Follow the primary source's mitigation guidance and check this record again before closing anything.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/drakkan/sftpgo/v2, github.com/drakkan/sftpgo.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GO-2026-6792 (OSV record GO-2026-6792 lists affected ranges: Go github.com/drakkan/sftpgo >=0; Go github.com/drakkan/sftpgo/v2 >=0 <2.7.5 (fixed))
- Verified: https://osv.dev/vulnerability/GHSA-q7pc-356p-hggc (OSV record GHSA-q7pc-356p-hggc lists affected ranges: Go github.com/drakkan/sftpgo/v2 >=0 <2.7.5 (fixed))
- Verified: https://github.com/advisories/GHSA-q7pc-356p-hggc (GitHub-reviewed advisory GHSA-q7pc-356p-hggc lists affected ranges: Go github.com/drakkan/sftpgo/v2 >=0 <=2.7.4)

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