mutagen: Improper Encoding or Escaping of Output
CVE-2023-30844 is a high-severity improper encoding or escaping of output vulnerability in mutagen from Mutagen-io, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected mutagen versions: github.com/mutagen-io/mutagen < 0.16.6; github.com/mutagen-io/mutagen >= 0.17.0, < 0.17.1; github.com/mutagen-io/mutagen-compose < 0.17.1. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.74% chance of exploitation within 30 days, higher than 55% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Mutagen Compose to 0.17.1 or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Mutagen-io | mutagen | github.com/mutagen-io/mutagen < 0.16.6; github.com/mutagen-io/mutagen >= 0.17.0, < 0.17.1; github.com/mutagen-io/mutagen-compose < 0.17.1 | Not stated |
| Mutagen | Mutagen Compose | before 0.17.1 | 0.17.1 |
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
- 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:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 3.0 | Low | CNA (github.com) |
| CVSS 3.1 | 8.8 | High | NVD |
Official description
Mutagen provides real-time file synchronization and flexible network forwarding for developers. Prior to versions 0.16.6 and 0.17.1 in `mutagen` and prior to version 0.17.1 in `mutagen-compose`, Mutagen `list` and `monitor` commands are susceptible to control characters that could be provided by remote endpoints. This could cause terminal corruption, either intentional or unintentional, if these characters were present in error messages or file paths/names. This could be used as an attack vector if synchronizing with an untrusted remote endpoint, synchronizing files not under control of the user, or forwarding to/from an untrusted remote endpoint. On very old systems with terminals susceptible to issues such as CVE-2003-0069, the issue could theoretically cause code execution. The problem has been patched in Mutagen v0.16.6 and v0.17.1. Earlier versions of Mutagen are no longer supported and will not be patched. Versions of Mutagen after v0.18.0 will also have the patch merged. As a workaround, avoiding synchronization of untrusted files or interaction with untrusted remote endpoints should mitigate any risk.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Encoding or Escaping of Output
The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved.
How developers prevent this class of flaw
- Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using the ESAPI Encoding control or a similar tool, library, or framework. These will help the programmer encode outputs in a manner less prone to error. Alternately, use built-in functions, but consider using wrappers in case those functions are discovered to have a vulnerability.
- If available, use structured mechanisms that automatically enforce the separation between data and code. These mechanisms may be able to provide the relevant quoting, encoding, and validation automatically, instead of relying on the developer to provide this capability at every point where output is generated. For example, stored procedures can enforce database query structure and reduce the likelihood of SQL injection.
- Understand the context in which your data will be used and the encoding that will be expected. This is especially important when transmitting data between different components, or when generating outputs that can contain multiple encodings at the same time, such as web pages or multi-part mail messages. Study all expected communication protocols and data representations to determine the required encoding strategies.
More Improper Encoding or Escaping of Output vulnerabilities (CWE-116)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- github.com/mutagen-io/mutagen/releases/tag/v0.16.6Release Notes
- github.com/mutagen-io/mutagen/releases/tag/v0.17.1Release Notes
Recent Improper Encoding or Escaping of Output vulnerabilities
- 7.5 High severity
- 9.8 Critical severity
- 9.8 Critical severity
- 8.8 High severity
- 7.8 High severity
- 7.5 High severity
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