ASUS RT-AX55 Routers OS Command Injection Vulnerability
ASUS · RT-AX55 Routers
ASUS RT-AX55 routers running firmware 3.0.0.4.386.51598 contain an OS command injection flaw in the /start_apply.htm handler, where the qos_bw_rulelist parameter is not properly sanitised before being passed to the operating system. An attacker who can reach the device over the network and holds valid credentials can inject arbitrary operating system commands through this parameter, with no user interaction required.
On ASUS RT-AX55 3.0.0.4.386.51598 devices, authenticated attackers can perform OS command injection via the /start_apply.htm qos_bw_rulelist parameter. NOTE: for the similar "token-generated module" issue, see CVE-2023-41345; for the similar "token-refresh module" issue, see CVE-2023-41346; for the similar "check token module" issue, see CVE-2023-41347; and for the similar "code-authentication module" issue, see CVE-2023-41348.
- Exploited
- Yes, in CISA KEV
- Reports
- 0
- Tactics
- 7/15
How an attack unfolds
Based on MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. mappings. Select a step to see the evidence.How attackers get in
What they do
What can follow
Exploitation timelineDated milestones for a CVE: when it was disclosed, when exploit code became public, when exploitation was confirmed, and when threat reports named it.
First seen exploited 21 months after disclosure.
- Disclosedday 0
- First seen exploitedVulnCheck KEV evidence+21 mo
- Added to CISA KEVEU database agrees+21 mo
CISA KEV listing is when exploitation was confirmed, not necessarily the first attack.
MITRE ATT&CKA public catalogue of the techniques attackers use, maintained by MITRE. Patchfirst uses it to describe what attackers do with a vulnerability. techniques
5 TechniqueOne specific attacker behaviour in MITRE ATT&CK, such as T1190 “Exploit Public-Facing Application”. IDs with a dot, like T1059.004, are sub-techniques., grouped by TacticThe attacker’s goal at a stage of an attack in MITRE ATT&CK, such as Initial Access or Persistence. Each technique belongs to one or more tactics. in kill-chain order 5Resource DevelopmentTA0042
Attackers have gained access to affected ASUS routers by using brute-force login attempts and authentication bypasses, allowing them to inject and execute commands to enable SSH. Additionally, they can place a backdoor in the NVRAM.
Initial AccessTA0001
ExecutionTA0002
Lateral MovementTA0008
Detection
0 rules for this CVE · 102 general rules for its techniquesRules for this CVE
0Sigma ruleAn open, vendor-neutral detection rule for log data. Security teams convert Sigma rules into searches for their own SIEM. that reference CVE-2023-39780 directly.CVE-specific rules are not available in this build. Search SigmaHQ ↗
General rules for this CVE’s techniques
These detect the technique in general, not this specific vulnerability.
Obtain CapabilitiesT15882 general rules
Valid AccountsT107856 general rules
- Win Susp Computer Name Containing Samtheadmincriticaltest
- Account Created And Deleted Within A Close Time Framehightest
- Activity From Anonymous IP Addresshightest
- Atypical Travelhightest
- Azure AD Threat Intelligencehightest
- Azure Subscription Permission Elevation Via AuditLogshightest
- External Remote SMB Logon from Public IPhightest
- Impossible Travelhightest
External Remote ServicesT113320 general rules
- External Remote SMB Logon from Public IPhightest
- OpenCanary - SSH Login Attempthightest
- OpenCanary - SSH New Connection Attempthightest
- OpenCanary - Telnet Login Attempthightest
- Running Chrome VPN Extensions via the Registry 2 VPN Extensionhightest
- Unusual Child Process of dns.exehightest
- Unusual File Deletion by Dns.exehightest
- Unusual File Modification by dns.exehightest
Unix ShellT1059.00419 general rules
- Linux Reverse Shell Indicatorcriticaltest
- AWS EC2 Startup Shell Script Changehightest
- Equation Group Indicatorshightest
- JexBoss Command Sequencehightest
- Shell Invocation via Env Command - Linuxhightest
- Suspicious Activity in Shell Commandshightest
- Suspicious Reverse Shell Command Linehightest
- Axios NPM Compromise Indicators - Linuxhighexperimental
SSHT1021.0045 general rules
- Bitbucket Global SSH Settings Changedmediumtest
- Bitbucket User Login Failure Via SSHmediumtest
- OpenSSH Server Listening On Socketmediumtest
- Port Forwarding Activity Via SSH.EXEmediumtest
- OpenEDR Spawning Command Shellmediumexperimental
Sigma rules © SigmaHQ, Detection Rule License 1.1; linked, not reproduced.
What security researchers reported
Not named in any threat report yetAlso mentioned in 50 community threat pulses (AlienVault OTX)
Weaker evidencePulses are indicator collections that anyone can publish. A mention is not confirmation of exploitation.
- Actively_Exploited_Kev | Oct 29, 202628 Oct 2026
- Actively_Exploited_Kev | Oct 28, 202627 Oct 2026
- Actively_Exploited_Kev | Oct 27, 202626 Oct 2026
- Actively_Exploited_Kev | Oct 24, 202623 Oct 2026
- Actively_Exploited_Kev | Oct 23, 202622 Oct 2026
- Actively_Exploited_Kev | Oct 22, 202621 Oct 2026
- 44 more on OTX