9.8Critical
CVE-2026-53611
Looking Glass is a modern, stateless network-diagnostic platform — a single self-contained Go binary that fronts a fleet of routers over SSH and exposes ping / traceroute / BGP lookups through a gRPC (ConnectRPC) API, an embedded SvelteKit web UI, and a lg-cli client. Prior to version 1.3.5, there is an OS Command Injection vulnerability resulting from an unanchored regular expression in the input validation layer. This issue has been patched in version 1.3.5.
What this means for your business
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 1% chance of attack attempts being seen in the next 30 days, ranking above 62% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.
Scoring
- CVSS
- 9.8 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- Weakness
- CWE-78
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-09-02
- Last modified
- 2026-09-09
- Sources
- NVD