How severe is CVE-2002-0518?

CVE-2002-0518 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2002-0518 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2002-0518?

CVE-2002-0518 primarily affects Freebsd. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2002-0518?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2002-0518 published?

CVE-2002-0518 was published on 2002-08-12 and last updated on 2026-06-16.

CVE-2002-0518

CVE-2002-0518 is a medium-severity vulnerability in Freebsd with a CVSS 2.0 base score of 5.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 2% (83rd percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Freebsd
Published: 2002-08-12
Last modified: 2026-06-16

Description

The SYN cache (syncache) and SYN cookie (syncookie) mechanism in FreeBSD 4.5 and earlier allows remote attackers to cause a denial of service (crash) (1) via a SYN packet that is accepted using syncookies that causes a null pointer to be referenced for the socket's TCP options, or (2) by killing and restarting a process that listens on the same socket, which does not properly clear the old inpcb pointer on restart.

Frequently asked questions

What is CVE-2002-0518?: The SYN cache (syncache) and SYN cookie (syncookie) mechanism in FreeBSD 4.5 and earlier allows remote attackers to cause a denial of service (crash) (1) via a SYN packet that is accepted using syncookies that causes a null pointer to be referenced for the socket's TCP options, or (2) by killing and restarting a process that listens on the same socket, which does not properly clear the old inpcb pointer on restart.
How severe is CVE-2002-0518?: CVE-2002-0518 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2002-0518 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2002-0518?: CVE-2002-0518 primarily affects Freebsd. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2002-0518?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2002-0518 published?: CVE-2002-0518 was published on 2002-08-12 and last updated on 2026-06-16.

References

Affected products (2)

cpe:2.3:o:freebsd:freebsd:4.5:release:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:4.5:stable:*:*:*:*:*:*

More vulnerabilities in Freebsd

CVE-2024-43102 — Critical (CVSS 10.0): Concurrent removals of certain anonymous shared memory mappings by using the UMTX_SHM_DESTROY sub-request of…
CVE-2018-17160 — Critical (CVSS 10.0): In FreeBSD before 11.2-STABLE(r341486) and 11.2-RELEASE-p6, insufficient bounds checking in one of the device models…
CVE-2014-3954 — Critical (CVSS 10.0): Stack-based buffer overflow in rtsold in FreeBSD 9.1 through 10.1-RC2 allows remote attackers to cause a denial of…
CVE-2011-4862 — Critical (CVSS 10.0): Buffer overflow in libtelnet/encrypt.c in telnetd in FreeBSD 7.3 through 9.0, MIT Kerberos Version 5 Applications (aka…
CVE-2006-4304 — Critical (CVSS 10.0): Buffer overflow in the sppp driver in FreeBSD 4.11 through 6.1, NetBSD 2.0 through 4.0 beta before 20060823, and…
CVE-2006-0226 — Critical (CVSS 10.0): Integer overflow in IEEE 802.11 network subsystem (ieee80211_ioctl.c) in FreeBSD before 6.0-STABLE, while scanning for…

All CVEs affecting Freebsd →