Vulnerability · Published Aug 5, 2026 · Assigned by VulnCheck

CVE-2026-70615boringproxy 0.10.0 SSH authorized_keys Injection via Tunnel Creation

Critical 9.9

In plain English

A critical-severity security flaw in boringproxy from boringproxy. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 29% of all known vulnerabilities).

Severity (CVSS 3.1)9.9Critical

Exploit odds (30 days)0.4%top 71.1% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

boringproxy through 0.10.0 contains a newline injection vulnerability that allows authenticated low-privileged users with tunnel-creation permission to inject arbitrary lines into the server account's SSH authorized_keys file by supplying a percent-encoded newline character in the domain parameter of the tunnel creation endpoint. Attackers can insert an unrestricted public key entry into authorized_keys to gain persistent shell access, and subsequently read cleartext credentials from the database file including all user tokens, tunnel private keys, and TLS certificates.

Affected products (as reported)

Vendor	Product	Versions
boringproxy	boringproxy	0 – through 0.10.0

Weakness: CWE-93 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

References

Researcher Disclosure technical-description, exploit
https://www.vulncheck.com/advisories/boringproxy-ssh-authorized-keys-injection-via-tunnel-creation third-party-advisory