In FreeBSD 12.0-STABLE before r349197 and 12.0-RELEASE before 12.0-RELEASE-p6, a bug in the non-default RACK TCP stack can allow an attacke…

published 2019-07-02 7y ago modified 2026-06-17 4mo ago also EUVD-2019-15174

cvss: 7.5; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 5.1%; EPSS 5.1% chance of exploitation in 30 days, percentile 92%
public exploits: 0; none known

In FreeBSD 12.0-STABLE before r349197 and 12.0-RELEASE before 12.0-RELEASE-p6, a bug in the non-default RACK TCP stack can allow an attacker to cause several linked lists to grow unbounded and cause an expensive list traversal on every packet being processed, leading to resource exhaustion and a denial of service.

Patch / fix

links 1

seclists.org/bugtraq/2019/Jun/27 advisory

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Exploit prediction

5.09% chance of exploitation in the next 30 days, higher than 92% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.0	7.5	CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	2.0	7.8	AV:N/AC:L/Au:N/C:N/I:N/A:C

Affected products

n/a FreeBSD

Classification

Weakness

CWE-770 Allocation of Resources Without Limits or Throttling

References

seclists.org /bugtraq/2019/Jun/27
mailing-list, mitigation, patch, third-party-advisory
security.freebsd.org /advisories/FreeBSD-SA-19:08.rack.asc
vendor-advisory, mitigation
openwall.com /lists/oss-security/2019/06/17/5
mailing-list, third-party-advisory
github.com /Netflix/security-bulletins/blob/master/advisories/third-party/2019-001.md
mitigation, third-party-advisory
packetstormsecurity.com /files/153329/Linux-FreeBSD-TCP-Based-Denial-Of-Service.html
third-party-advisory, vdb-entry
kb.cert.org /vuls/id/905115
third-party-advisory, us-government-resource
packetstormsecurity.com /files/153378/FreeBSD-Security-Advisory-FreeBSD-SA-19-08.rack.html
third-party-advisory, vdb-entry
support.f5.com /csp/article/K75521003
third-party-advisory
kb.pulsesecure.net /articles/Pulse_Security_Advisories/SA44193
third-party-advisory
security.netapp.com /advisory/ntap-20190625-0004/
third-party-advisory

Sources

CVE List CVE-2019-5599
NVD CVE-2019-5599

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