CVE-2026-39834
Last modified
CVE-2026-39834 is a critical-severity vulnerability rated 9.1/10 on the CVSS scale. When writing data larger than 4GB in a single Write call on an SSH channel, an integer overflow in the internal payload size calculation caused the write loop to spin indefinitely, sending empty packets without making progress. The size comparison now uses int64 to prevent truncation.. EPSS estimates a 0.47% chance of exploitation in the next 30 days.
Description
When writing data larger than 4GB in a single Write call on an SSH channel, an integer overflow in the internal payload size calculation caused the write loop to spin indefinitely, sending empty packets without making progress. The size comparison now uses int64 to prevent truncation.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Golang | Crypto | < 0.52.0 |
References
- https://go.dev/cl/781663Issue Tracking
- https://go.dev/issue/79567Issue Tracking
- https://pkg.go.dev/vuln/GO-2026-5020Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
Frequently Asked Questions
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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