CVE-2019-11478

SACK can cause extensive memory use via fragmented resend queue

At a glance

Severity
MEDIUM 5.3
EPSS
EPSS 94.69 % · percentile 100 (2026-10-27)
State
PUBLISHED
Published
Updated
Assigner
canonical
NVD status
Modified

Description

Jonathan Looney discovered that the TCP retransmission queue implementation in tcp_fragment in the Linux kernel could be fragmented when handling certain TCP Selective Acknowledgment (SACK) sequences. A remote attacker could use this to cause a denial of service. This has been fixed in stable kernel releases 4.4.182, 4.9.182, 4.14.127, 4.19.52, 5.1.11, and is fixed in commit f070ef2ac66716357066b683fb0baf55f8191a2e.

Scores

VersionScoreVectorScored by
CVSS 3.0MEDIUM 5.3CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Lcanonical
CVSS 3.0MEDIUM 5.3CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:LNVD · security@ubuntu.com (Secondary)
CVSS 3.0HIGH 7.5CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HNVD · nvd@nist.gov (Primary)
CVSS 2.0MEDIUM 5.0AV:N/AC:L/Au:N/C:N/I:N/A:PNVD · nvd@nist.gov (Primary)

Weaknesses (CWE)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
Linux · Linux kernelaffected 4.4 < 4.4.182 ; affected 4.9 < 4.9.182 ; affected 4.14 < 4.14.127 ; affected 4.19 < 4.19.52 ; affected 5.1 < 5.1.11

References

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD