CVE-2017-7521
CVE-2017-7521 is a medium-severity vulnerability in Openvpn with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-415.
Key facts
- Severity: Medium (CVSS 3.x base score 5.9)
- CVSS v2: 4.3
- EPSS exploit prediction: 4% (89th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-415
- Affected product: Openvpn
- Published:
- Last modified:
Description
OpenVPN versions before 2.4.3 and before 2.3.17 are vulnerable to remote denial-of-service due to memory exhaustion caused by memory leaks and double-free issue in extract_x509_extension().
Frequently asked questions
- What is CVE-2017-7521?
- OpenVPN versions before 2.4.3 and before 2.3.17 are vulnerable to remote denial-of-service due to memory exhaustion caused by memory leaks and double-free issue in extract_x509_extension().
- How severe is CVE-2017-7521?
- CVE-2017-7521 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2017-7521 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (89th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2017-7521?
- CVE-2017-7521 primarily affects Openvpn. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2017-7521?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2017-7521 published?
- CVE-2017-7521 was published on 2017-06-27 and last updated on 2026-06-17.
References
- http://www.debian.org/security/2017/dsa-3900
- http://www.securityfocus.com/bid/99230
- http://www.securitytracker.com/id/1038768
- https://community.openvpn.net/openvpn/wiki/VulnerabilitiesFixedInOpenVPN243
Affected products (9)
- cpe:2.3:a:openvpn:openvpn:*:*:*:*:*:*:*:*
- cpe:2.3:a:openvpn:openvpn:2.4.0:*:*:*:*:*:*:*
- cpe:2.3:a:openvpn:openvpn:2.4.0:alpha2:*:*:*:*:*:*
- cpe:2.3:a:openvpn:openvpn:2.4.0:beta1:*:*:*:*:*:*
- cpe:2.3:a:openvpn:openvpn:2.4.0:beta2:*:*:*:*:*:*
- cpe:2.3:a:openvpn:openvpn:2.4.0:rc1:*:*:*:*:*:*
- cpe:2.3:a:openvpn:openvpn:2.4.0:rc2:*:*:*:*:*:*
- cpe:2.3:a:openvpn:openvpn:2.4.1:*:*:*:*:*:*:*
- cpe:2.3:a:openvpn:openvpn:2.4.2:*:*:*:*:*:*:*
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- CVE-2026-43414 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: scsi: qla2xxx: Completely fix fcport double…
- CVE-2026-43011 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: net/x25: Fix potential double free of skb When…
- CVE-2026-31609 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: smb: client: avoid double-free in…