Resource exhaustion in FreeBSD
CVE-2018-6922
One of the data structures that holds TCP segments in all versions of FreeBSD prior to 11.2-RELEASE-p1, 11.1-RELEASE-p12, and 10.4-RELEASE-p10 uses an inefficient algorithm to reassemble the data. This causes the CPU time spent on segment processing to grow linearly with the number of segments in the reassembly queue. An attacker who has the ability to send TCP traffic to a victim system can degrade the victim system's network performance and/or consume excessive CPU by exploiting the inefficiency of TCP reassembly handling, with relatively small bandwidth cost.
Vulnerability class: DoS (Denial of Service)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.
EPSS exploit prediction
EPSS: 0.032 (87.8th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 88th percentile — 87.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.032 · newest: 0.032 · change: 0.000
Affected products
- FreeBSD — versions 11.1, 11.2, 10.4
Weakness classification (CWE)
References
- www.freebsd.org/security/advisories/FreeBSD-SA-18:08.tcp.asc (vendor-advisory, Patch, Vendor Advisory)
- www.securitytracker.com/id/1041425 (VDB Entry, Third Party Advisory, vdb-entry)
- www.oracle.com/technetwork/security-advisory/cpujan2019-5072801.html (Patch)
- www.securityfocus.com/bid/105058 (VDB Entry, Third Party Advisory, vdb-entry)
- security.netapp.com/advisory/ntap-20180815-0002/ (Third Party Advisory)
Frequently asked questions
- What is CVE-2018-6922?
- CVE-2018-6922 is a medium-severity vulnerability in FreeBSD, classified under Uncontrolled Resource Consumption. CVSS score: 5.3/10. Published 2018-08-09.
- How severe is CVE-2018-6922?
- Medium severity. CVSS v3 base score is 5.3 out of 10.