@amazon-codecatalyst/blueprints.blueprint: Improper Neutralization of Special Elements used in an OS Command
CVE-2026-85012 is a high-severity improper neutralization of special elements used in an OS command vulnerability in @amazon-codecatalyst/blueprints.blueprint from AWS, with a CVSS 3.1 base score of 8.0 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, but only if a user takes part, for example by opening a link or file. The record lists version 0.3.156 as the first without the flaw, so updating @amazon-codecatalyst/blueprints.blueprint to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 2.26% chance of exploitation within 30 days, higher than 83% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update @amazon-codecatalyst/blueprints.blueprint to 0.3.156 or a later version.
- Read the advisory on aws.amazon.com for workarounds and exact fixed builds.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| AWS | @amazon-codecatalyst/blueprints.blueprint | before 0.3.156 | 0.3.156 |
Version data comes from the organisation that assigned the CVE. 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
- LowA basic user account is enough.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- 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:L/UI:R/S:U/C:H/I:H/A:H. Scored by CNA.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.5 | High | CNA |
| CVSS 3.1 | 8.0 | High | CNA |
Official description
Improper neutralization of special elements used in an OS command (CWE-78) in the blueprint resynthesis framework in Amazon Web Services codecatalyst-blueprints before 0.3.156 might allow a user with permission to commit to a repository in the project to execute arbitrary commands in the blueprint resynthesis environment via shell metacharacters in the owner field of a [local] merge strategy entry in a crafted .ownership-file. Version 0.3.156 removes shell interpretation of the owner field, running the command directly rather than through a shell, and rejects values outside an allowlisted command form. This eliminates shell metacharacter command injection. To remediate this issue, users should upgrade to version 0.3.156 or later. No action is required for use of the Amazon CodeCatalyst service. Resynthesis runs in an isolated per-project environment with scoped credentials, and the service applies server-side validation there that rejects [local] merge strategy commands outside a restricted allowlisted form, including for blueprint versions published before 0.3.156.
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
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Advisories
Recent Improper Neutralization of Special Elements used in an OS Command vulnerabilities
- 7.8 High severity
- 9.8 Critical severity
- 9.8 Critical severity
- 8.8 High severity
- 8.4 High severity
- 8.8 High severity
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