# Tinfoil Factory netfoil log injection via unvalidated domain names

Source: https://junglewise.ai/threats/tinfoil-factory-netfoil-log-injection-via-unvalidated-domain-names-020d7d32  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-07. Updated: 2026-07-07  
License: CC BY 4.0 with a link back

Severity: low · CVSS 2.3 · Published 2026-07-07

The netfoil library, used for network-related operations in Go applications, fails to properly clean domain names before writing them to system logs. This could allow an attacker to inject misleading information or special characters into logs, potentially complicating incident investigations or affecting automated log-monitoring tools. The impact depends on how your organization processes and views these logs.

Technologies: [github.com/tinfoil-factory/netfoil (Go)](https://junglewise.ai/threats/technologies/github-com-tinfoil-factory-netfoil), [Tinfoil Factory Netfoil](https://junglewise.ai/threats/technologies/netfoil). Vendors: [Go](https://junglewise.ai/threats/vendors/go), [Tinfoil Factory](https://junglewise.ai/threats/vendors/tinfoil-factory).

## Quick answers

**Is This vulnerability exploited in the wild?** No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.

**How severe is This vulnerability?** Low severity, with a CVSS score of 2.3, published 7 July 2026.

**Which products and versions are affected?** github.com/tinfoil-factory/netfoil (Go) < 0.3.0; Tinfoil Factory Netfoil < 0.3.0.

**Is there a fix for This vulnerability?** A patch was published on 2026-07-07: Version 0.3.0 released Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is This vulnerability attacked?** It is attacked over the network, in a software library.

**Am I affected?** Check whether you run github.com/tinfoil-factory/netfoil (Go) or Tinfoil Factory Netfoil at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A log injection vulnerability (CWE-117) exists in netfoil versions prior to 0.3.0. The library constructs log messages using external domain name input without neutralizing special characters or validating the input against allowed character sets. An attacker with network access and low privileges can provide crafted domain names that are subsequently written to the logs. This can be used to forge log entries or inject malicious content that may be interpreted by log management software. The issue is resolved in version 0.3.0.

## Affected products

- tinfoil-factory netfoil < 0.3.0

## Timeline

- 2026-05-31: disclosed: Initial report by stigtsp
- 2026-07-07: advisory: GitHub Advisory published
- 2026-07-07: patched: Version 0.3.0 released

## References

- [https://api.github.com/users/stigtsp](https://api.github.com/users/stigtsp)
- [https://github.com/stigtsp](https://github.com/stigtsp)
- [https://api.github.com/users/stigtsp/gists%7B/gist_id%7D](https://api.github.com/users/stigtsp/gists%7B/gist_id%7D)
- [https://api.github.com/users/stigtsp/repos](https://api.github.com/users/stigtsp/repos)
- [https://avatars.githubusercontent.com/u/75371?v=4](https://avatars.githubusercontent.com/u/75371?v=4)
- [https://api.github.com/users/stigtsp/events%7B/privacy%7D](https://api.github.com/users/stigtsp/events%7B/privacy%7D)

## Related threats

- [Netfoil TTL not decremented in DNS responses](https://junglewise.ai/threats/go-2026-6906-netfoil-doesn-t-decrement-ttl-in-github-com-tinfoil-a5094761)
- [Netfoil TTL decrement logic flaw](https://junglewise.ai/threats/netfoil-doesn-t-decrement-ttl-f0272cfd)
- [GO-2026-6277 - netfoil vulnerable to improper handling of untrusted DoH response data in github.com/tinfoil-factory/netfoil](https://junglewise.ai/threats/go-2026-6277-netfoil-vulnerable-to-improper-handling-of-untrusted-doh-3c188b0a)
- [netfoil improper output neutralization for logs in DoH response handling](https://junglewise.ai/threats/netfoil-improper-output-neutralization-for-logs-in-doh-response-c6a8161c)
- [GO-2026-6143 - netfoil: Incorrect block responses could lead to localhost traffic in github.com/tinfoil-factory/netfoil](https://junglewise.ai/threats/go-2026-6143-netfoil-incorrect-block-responses-could-lead-to-localhost-10a9eea0)