CyberSecBulletin
CVE-2026-30303NVD status: Analyzed

Axon Code: Improper Neutralization of Special Elements used in an OS Command

Published Updated By the CyberSecBulletin desk

CVE-2026-30303 is a critical-severity improper neutralization of special elements used in an OS command vulnerability in Axon Code from Matterai, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Axon Code versions: 4.123.1 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.46% chance of exploitation within 30 days, higher than 74% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of Axon Code you run against the affected versions below, and install the vendor's latest release.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
MatteraiAxon Code4.123.1 and earlierNot stated

Version data comes from NVD's product matching. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CISA (ADP).

Official 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.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Neutralization of Special Elements used in an OS Command

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 before it is sent to a downstream component.

How developers prevent this class of flaw

  • If at all possible, use library calls rather than external processes to recreate the desired functionality.
  • 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.
  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

More Improper Neutralization of Special Elements used in an OS Command vulnerabilities (CWE-78)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Improper Neutralization of Special Elements used in an OS Command vulnerabilities

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