CVE-2026-84268
HIGH 8.8A flaw was found in the SFTP backend in gvfs. When mounting a share and reading a file, a malicious SFTP server can cause read_reply() to process a length that exceeds the size requested by the client. The function does not verify the server-provided length against the allocated buffer size, causing the operation to write past the intended boundaries. This issue allows a malicious server to corrupt adjacent heap memory in the gvfsd-sftp process, resulting in a denial of service as the process aborts upon detecting the heap corruption or potentially allowing arbitrary code execution.
Severe if exploited (CVSS 8.8), but no known exploitation and low modeled probability. Patch on a normal cadence.
Exploitation likelihood
0.3%chance of exploitation in 30 days · 25th percentile
Impact if exploited
8.8CVSS 3.1 · HIGH
- ConfidentialityHigh
- IntegrityHigh
- AvailabilityHigh
What an attacker needs
- ✓Access: Reachable over the network — no local access needed
- ✓Privileges: No account or privileges required
- ⚠User interaction: A user must take an action (click / open a file)
- ✓Complexity: No special conditions — reliably repeatable
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-84268/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-84268/poc.json
Affected
Products Gvfs Red Hat Enterprise Linux 10 Red Hat Enterprise Linux 6 Red Hat Enterprise Linux 7 Red Hat Enterprise Linux 8 Red Hat Enterprise Linux 9
Weakness (CWE)
- CWE-122: Heap-based Buffer Overflow
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
All CVSS metrics
- HIGH 8.8 v3.1 · CNA Primary
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - HIGH 8.8 v3.1 · NVD Secondary
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H