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 (involving hex strings) that is mishandled in the _yr_re_emit function, a different vulnerability than CVE-2017-9304.

Published: 2017-06-05 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2017-9438 is rated Moderate Risk (61/100): CVSS High severity, with medium exploitation likelihood (EPSS 2.57%). Core evidence: EPSS rose +1.96% over the last day, indicating growing attacker interest. 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.

Exploit prediction scoring system (EPSS) score for CVE-2017-9438

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 2026-06-15 0.61% 2.57% +1.96%
2 2025-03-30 1.47% 0.61% -0.86%
3 2025-03-29 1.47%

Full EPSS history (11 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-9438

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.0 HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
10.0 2.9 [email protected]

Weakness enumeration for CVE-2017-9438

OS Trackers for CVE-2017-9438

vendor priority summary link
debian low CVE-2017-9438 low 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-2017-9438
ubuntu low CVE-2017-9438 low 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-2017-9438

Affected software / configurations for CVE-2017-9438

Vendor Product Version Raw CPE
virustotal yara 3.5.0 cpe:2.3:a:virustotal:yara:3.5.0:*:*:*:*:*:*:*

References for CVE-2017-9438

cvelogic Threat Intelligence