Double CVSS 9.9 Day: BeyondTrust Backdoored, Roundcube Weaponized, and Supply Chain Hit Again

February 21 is shaping up as one of the nastiest security days of 2026. Two separate critical vulnerabilities — both scoring CVSS 9.9 — are actively being exploited in the wild simultaneously. BeyondTrust's CVE-2026-1731 is being hammered across financial, legal, healthcare, and tech sectors in the US, France, Germany, Australia, and Canada. Unit 42 confirmed attackers are using it to drop VShell, deploy web shells, establish C2, move laterally, and exfiltrate data. That's the full kill chain, not just initial access.

Meanwhile CISA added two Roundcube webmail flaws to the KEV catalog — including CVE-2025-49113 (CVSS 9.9), a deserialization RCE that attackers weaponized within 48 hours of public disclosure. Webmail servers are soft targets because they're internet-facing and often deprioritized for patching. The rapid weaponization timeline here is alarming.

On the supply chain front, the Cline CLI 2.3.0 incident confirms the npm ecosystem remains a high-value attack vector. A compromised publish token let attackers silently install OpenClaw on developer machines via postinstall script. No malicious payload observed this time — but the access was there. Anthropic dropped a counter-punch: Claude Code Security, now in limited preview, uses AI to scan codebases for vulnerabilities. The irony of AI being used to attack and defend simultaneously is no longer theoretical — it's the daily operational reality.

Impact Score

9/10

Key Stories

BeyondTrust CVE-2026-1731 Exploited for Web Shells, Backdoors, Full Kill Chain

The Hacker News / Palo Alto Unit 42

CISA Adds Two Roundcube Flaws to KEV — CVE-2025-49113 CVSS 9.9 Weaponized in 48 Hours

The Hacker News / CISA

Cline CLI 2.3.0 Supply Chain Attack Silently Installed OpenClaw on Dev Machines

The Hacker News

Anthropic Launches Claude Code Security — AI-Powered Vuln Scanning for Codebases

The Hacker News / Anthropic

MIMICRAT ClickFix Campaign Deploys Custom C++ RAT via Compromised Sites

Elastic Security Labs / The Hacker News

Analyst Take

Two simultaneous CVSS 9.9 exploits in active use is not coincidence — it signals threat actors are running parallel campaigns, likely testing defender response bandwidth. When your SOC is handling BeyondTrust, Roundcube drops on the same day, and your dev team just got hit by a supply chain attack, triage breaks down. That's the play. The Cline CLI incident deserves more attention than it's getting: no malicious payload this time, but npm postinstall is a trusted execution path and attackers just proved they can reach it. Claude Code Security launching the same week is either very good timing or very good intel. Either way — patch BeyondTrust and Roundcube now, audit your npm dependencies, and assume developer workstations in your org are already a target.