CVE-2019-11478CWE-770

SACK can cause extensive memory use via fragmented resend queue

Medium · published June 18, 2019

Patch now

High probability of exploitation

CVSS calls it medium at 5.3. It sits in the 99.9th percentile for exploit probability.

CVSS v3.0

5.3

EPSS

95%

Percentile

99.9

In the wild

Unconfirmed

What it is

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.

The record

Technical detail

CVSS v3.0: 5.3 · MEDIUM
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CVSS v4.0: Not supplied
EPSS: 0.94686 · 99.9th percentile
Weakness: CWE-770 · Allocation of Resources Without Limits or Throttling
Published: 2019-06-18T23:34Z

EPSS history

Timeline

18 JUN 23:34Z
SACK can cause extensive memory use via fragmented resend queue
cvelistv5