How severe is CVE-2018-17155?

CVE-2018-17155 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2018-17155 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-17155?

CVE-2018-17155 primarily affects Freebsd. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-17155?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2018-17155 published?

CVE-2018-17155 was published on 2018-09-28 and last updated on 2026-06-17.

CVE-2018-17155

CVE-2018-17155 is a medium-severity vulnerability in Freebsd with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-200.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 2.1
EPSS exploit prediction: 0% (29th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-200
Affected product: Freebsd
Published: 2018-09-28
Last modified: 2026-06-17

Description

In FreeBSD before 11.2-STABLE(r338983), 11.2-RELEASE-p4, 11.1-RELEASE-p15, 10.4-STABLE(r338984), and 10.4-RELEASE-p13, due to insufficient initialization of memory copied to userland in the getcontext and swapcontext system calls, small amounts of kernel memory may be disclosed to userland processes. Unprivileged authenticated local users may be able to access small amounts privileged kernel data.

Frequently asked questions

What is CVE-2018-17155?: In FreeBSD before 11.2-STABLE(r338983), 11.2-RELEASE-p4, 11.1-RELEASE-p15, 10.4-STABLE(r338984), and 10.4-RELEASE-p13, due to insufficient initialization of memory copied to userland in the getcontext and swapcontext system calls, small amounts of kernel memory may be disclosed to userland processes. Unprivileged authenticated local users may be able to access small amounts privileged kernel data.
How severe is CVE-2018-17155?: CVE-2018-17155 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2018-17155 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-17155?: CVE-2018-17155 primarily affects Freebsd. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-17155?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-17155 published?: CVE-2018-17155 was published on 2018-09-28 and last updated on 2026-06-17.

References

https://security.FreeBSD.org/advisories/FreeBSD-EN-18:12.mem.asc

Affected products (5)

cpe:2.3:o:freebsd:freebsd:*:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:10.4:*:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:10.4:p13:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:11.1:p15:*:*:*:*:*:*
cpe:2.3:o:freebsd:freebsd:11.2:p4:*:*:*:*:*:*

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