Vulnerability in Opensrcsec Grsecurity

CVE-2019-5023

An exploitable vulnerability exists in the grsecurity PaX patch for the function read_kmem, in PaX from version pax-linux-4.9.8-test1 to 4.9.24-test7, grsecurity official from version grsecurity-3.1-4.9.8-201702060653 to grsecurity-3.1-4.9.24-201704252333, grsecurity unofficial from version v4.9.25-unofficialgrsec to v4.9.74-unofficialgrsec. PaX adds a temp buffer to the read_kmem function, which is never freed when an invalid address is supplied. This results in a memory leakage that can lead to a crash of the system. An attacker needs to induce a read to /dev/kmem using an invalid address to exploit this vulnerability.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.007 (53.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 53rd percentile — 53.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2019-5023: held from 0.007 to 0.007.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000

Affected products

  • Opensrcsec Grsecurity
  • Opensrcsec Pax
  • Pax — versions PaX pax-linux-4.9.24-test7.patch (latest version available to the public) grsecurity grsecurity-3.1-4.9.24-201704252333.patch (latest official version available to the public) v4.9.74-unofficial_grsec (latest unofficial version available to the public)

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2019-5023?
CVE-2019-5023 is a medium-severity vulnerability in Opensrcsec Grsecurity, classified under Missing Release of Memory after Effective Lifetime. CVSS score: 5.9/10. Published 2019-10-31.
How severe is CVE-2019-5023?
Medium severity. CVSS v3 base score is 5.9 out of 10.