VulnerabilityPublished 27 Mar 2026

CVE-2026-30303: OS Command Injection

Source CVE Database V5

Not known to be exploited · CVSS 9.8 Critical.

Data as of 26 Oct 2026, 13:47 UTC

CVSS 3.1 base score

9.8Critical

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 1.4% chance of exploitation in 30 days – higher than 72% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 27 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

AI-suggested

To mitigate CVE-2026-30303, organizations should immediately audit their use of Axon Code on Windows systems and disable or restrict the command auto-approval module until a patch is available. Avoid relying on the affected whitelist mechanism for command validation. Implement strict input validation and sanitization for any commands executed on Windows, ensuring that parsing logic matches the execution environment. Use Windows-native command parsing libraries or thoroughly test any cross-platform parsers for compatibility with Windows CMD escape sequences. Employ application whitelisting and endpoint detection and response (EDR) solutions to monitor and block suspicious command execution patterns, especially those involving command chaining operators like '&'. Network segmentation and least privilege principles should be enforced to limit the impact of potential exploitation. Stay alert for vendor updates or patches from Axon Code developers and apply them promptly once released. Conduct regular security assessments and penetration testing to detect similar injection flaws.

Description

The command auto-approval module in Axon Code contains an OS Command Injection vulnerability, rendering its whitelist security mechanism ineffective. The vulnerability stems from the incorrect use of an incompatible command parser (the Unix-based shell-quote library) to analyze commands on the Windows platform, coupled with a failure to correctly handle Windows CMD-specific escape sequences (^). Attackers can exploit this discrepancy between the parsing logic and the execution environment by constructing payloads such as git log ^" & malicious_command ^". The Axon Code parser is deceived by the escape characters, misinterpreting the malicious command connector (&) as being within a protected string argument and thus auto-approving the command. However, the underlying Windows CMD interpreter ignores the escaped quotes, parsing and executing the subsequent malicious command directly. This allows attackers to achieve arbitrary Remote Code Execution (RCE) after bypassing what appears to be a legitimate Git whitelist check.

Impact

The impact of CVE-2026-30303 is severe for organizations using Axon Code on Windows platforms. Successful exploitation allows attackers to execute arbitrary commands remotely, potentially leading to full system compromise. This can result in unauthorized data access, data modification or destruction, deployment of malware or ransomware, lateral movement within networks, and disruption of critical services. The bypass of the whitelist mechanism undermines a key security control, increasing the risk of undetected attacks. Organizations relying on Axon Code for command validation or automation are particularly vulnerable. The ease of exploitation without authentication or user interaction broadens the attack surface, making it attractive for attackers to target. If exploited in critical infrastructure, financial, healthcare, or government environments, the consequences could be catastrophic, including data breaches, operational downtime, and reputational damage.

Summary

CVE-2026-30303 is a critical OS Command Injection vulnerability found in the command auto-approval module of Axon Code, a tool that implements a whitelist mechanism to restrict command execution. The root cause is the use of a Unix-based shell-quote parsing library to analyze commands on Windows systems. This parser fails to correctly interpret Windows CMD-specific escape sequences, particularly the caret (^) character used for escaping. Attackers exploit this by crafting payloads such as 'git log ^" & malicious_command ^"', where the parser mistakenly treats the ampersand (&) as part of a quoted string, thus approving the command. However, the Windows CMD interpreter ignores the escaped quotes and executes the malicious command following the ampersand. This discrepancy allows attackers to bypass the whitelist and execute arbitrary commands remotely, leading to full remote code execution (RCE) capabilities. The vulnerability affects Windows environments running Axon Code with this flawed parsing logic. Although no specific affected versions or patches are listed, the vulnerability was published on March 27, 2026, with no CVSS score assigned yet. No known exploits have been reported in the wild, but the technical details indicate a high risk due to the ease of bypassing security controls and executing arbitrary code without authentication or user interaction.

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #9OWASP Top 10 A05:2025: Injection (opens in a new tab)
The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.
Architecture and Design
If at all possible, use library calls rather than external processes to recreate the desired functionality.
Architecture and Design · Operation · Sandbox or Jail
Run the code in a "jail" or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which files can be accessed in a particular directory or which commands can be executed by the software.
Architecture and Design · Attack Surface Reduction
For any data that will be used to generate a command to be executed, keep as much of that data out of external control as possible. For example, in web applications, this may require storing the data locally in the session's state instead of sending it out to the client in a hidden form field.
OWASP Cheat Sheets
Injection Prevention (opens in a new tab)
Injection Prevention in Java (opens in a new tab)
OS Command Injection Defense (opens in a new tab)
Abuse Case (opens in a new tab)
Deserialization (opens in a new tab)
OWASP ASVS 4.0.3
V12.3.5 (opens in a new tab)
V5.3.8 (opens in a new tab)
V1.5.1 (opens in a new tab)
Attack patterns
Command Line Execution through SQL Injection (opens in a new tab)
Command Delimiters (opens in a new tab)
Exploiting Multiple Input Interpretation Layers (opens in a new tab)
Argument Injection (opens in a new tab)
OS Command Injection (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 27 Mar 2026, 14:50 UTC

WeaknessesCWE-78

Technical details

References

Community reviews

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