Upstream information
Description
frp is a fast reverse proxy. From 0.53.0 until 0.70.1, frp's optional SSH Tunnel Gateway in pkg/ssh/server.go parses an SSH exec channel request by adding 4 to an attacker-controlled four-byte big-endian length. A length of 0xFFFFFFFF makes the uint32 addition wrap to 3, defeats the payload bounds check, and causes payload[4:3] to panic in TunnelServer.handleNewChannel. When no authorized-keys file is configured, sshConfig.NoClientAuth permits an unauthenticated peer to reach this channel phase before the frp token is checked, so a single five-byte request terminates the frps process and drops every active tunnel. This issue is fixed in version 0.70.1.SUSE information
Overall state of this security issue: Resolved
This issue is currently rated as having important severity.
| CVSS detail | CNA (GitHub) |
|---|---|
| Base Score | 8.7 |
| Vector | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| Attack Vector | Network |
| Attack Complexity | Low |
| Attack Requirements | None |
| Privileges Required | None |
| User Interaction | None |
| Vulnerable System Confidentiality Impact | None |
| Vulnerable System Integrity Impact | None |
| Vulnerable System Availability Impact | High |
| Subsequent System Confidentiality Impact | None |
| Subsequent System Integrity Impact | None |
| Subsequent System Availability Impact | None |
| CVSSv4 Version | 4.0 |
SUSE Security Advisories:
- SUSE-SU-2026:23625-1, published 2026-09-04T12:30:23Z
List of released packages
| Product(s) | Fixed package version(s) | References |
|---|---|---|
| SUSE Linux Enterprise Server 16.1 |
| Patchnames: SUSE Linux Enterprise Server 16.1 GA govulncheck-vulndb-0.0.20260916T180043-160100.1.1 (aarch64,ppc64le,s390x,x86_64) |
| SUSE Linux Enterprise Server for SAP applications 16.1 |
| Patchnames: SUSE Linux Enterprise Server for SAP applications 16.1 GA govulncheck-vulndb-0.0.20260916T180043-160100.1.1 (aarch64,ppc64le,s390x,x86_64) |
SUSE Timeline for this CVE
CVE page created: Fri Sep 4 16:52:18 2026CVE page last modified: Wed Oct 28 14:10:58 2026