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 that is mishandled in the _yr_re_emit function.
Conclusion & alert: CVE-2017-9304 is rated Moderate Risk (40/100): CVSS High severity, with low exploitation likelihood (EPSS 0.11%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-05-08 | 0.33% | 0.11% | -0.22% |
| 2 | 2025-11-21 | 0.36% | 0.33% | -0.02% |
| 3 | 2025-11-18 | — | 0.36% | — |
Full EPSS history (12 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.5 | 3.0 | HIGH |
|
3.9 | 3.6 | [email protected] |
| 5.0 | 2.0 | MEDIUM |
|
10.0 | 2.9 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
not yet assigned | CVE-2017-9304 not yet assigned priority: Debian including 1 source packages (yara), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. | https://security-tracker.debian.org/tracker/CVE-2017-9304 |
ubuntu
|
medium | CVE-2017-9304 medium priority: Ubuntu including 1 source packages (yara), 22 status rows across 22 suites (artful, bionic, cosmic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial, yakkety, zesty): not-affected 16, ignored 3, released 2, DNE 1. | https://ubuntu.com/security/CVE-2017-9304 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| virustotal | yara | 3.5.0 | cpe:2.3:a:virustotal:yara:3.5.0:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://github.com/VirusTotal/yara/commit/925bcf3c3b0a28b5b78e25d9efda5c0bf27ae699 | Patch |
| https://github.com/VirusTotal/yara/issues/674 | Issue Tracking Patch |