# CVE-2026-84268: GNOME gvfs SFTP backend heap overflow

Source: https://junglewise.ai/threats/cve-2026-84268-gnome-gvfs-sftp-backend-heap-overflow  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-01. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-84268 · Severity: high · CVSS 8.8 · Published 2026-09-01

GNOME Virtual File System (gvfs) is used to mount and access remote file shares, including SFTP servers. A malicious SFTP server can trigger a heap buffer overflow in the gvfsd-sftp process when a client reads a file, causing the service to crash or potentially allowing code execution. This could be exploited by attackers who control or intercept an SFTP connection to take down the file access service or gain unauthorized access to the affected system.

Technologies: [Gnome Gvfs](https://junglewise.ai/threats/technologies/gvfs). Vendors: [Gnome](https://junglewise.ai/threats/vendors/gnome).

## Quick answers

**Is CVE-2026-84268 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-84268 being exploited in the wild.

**How severe is CVE-2026-84268?** High severity, with a CVSS score of 8.8, published 1 September 2026.

**Which products and versions are affected?** Gnome Gvfs <UNKNOWN>.

**Is there a fix for CVE-2026-84268?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2026-84268 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-84268?** Check whether you run Gnome Gvfs at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability exists in the SFTP backend's read_reply() function, which processes responses from an SFTP server. The function fails to validate that the server-provided length value is consistent with the buffer size allocated by the client, leading to a heap buffer overflow. An attacker controlling a malicious SFTP server can respond to a client file read request with a length field exceeding the client's expected allocation, causing out-of-bounds memory writes. The attack vector is network-based and requires the victim to connect to the attacker's malicious SFTP server. This can result in heap memory corruption, denial of service (process abort), or potentially arbitrary code execution within the gvfsd-sftp process context.

## Affected products

- GNOME gvfs <UNKNOWN>

## Timeline

- 2026-09-01: disclosed

## References

- [https://gitlab.gnome.org/GNOME/gvfs](https://gitlab.gnome.org/GNOME/gvfs)
- [https://access.redhat.com/downloads/content/package-browser/](https://access.redhat.com/downloads/content/package-browser/)

## Related threats

- [GNOME gvfs privilege escalation via symlink TOCTOU in admin daemon](https://junglewise.ai/threats/cve-2026-88924-gnome-gvfs-privilege-escalation-via-symlink-toctou-in-admin)
- [GNOME gvfs buffer overflow in MTP backend](https://junglewise.ai/threats/cve-2026-84270-gnome-gvfs-buffer-overflow-in-mtp-backend)
- [GNOME gvfs AFP backend heap buffer overflow](https://junglewise.ai/threats/cve-2026-84269-gnome-gvfs-afp-backend-heap-buffer-overflow)
- [GNOME gvfs SFTP buffer read vulnerability](https://junglewise.ai/threats/cve-2026-84267-gnome-gvfs-sftp-buffer-read-vulnerability)