CVE-2018-15686: systemd: reexec state injection: fgets() on overlong lines leads to line splitting

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.3% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2018-10-26 · updated 2026-06-17
Weakness: CWE-502

Description

A vulnerability in unit_deserialize of systemd allows an attacker to supply arbitrary state across systemd re-execution via NotifyAccess. This can be used to improperly influence systemd execution and possibly lead to root privilege escalation. Affected releases are systemd versions up to and including 239.

Affected products

Canonical Ubuntu Linux: 16.04, 18.04, 18.10
Debian Linux: 8.0
Oracle Communications Cloud Native Core Network Function Cloud Native Environment: 1.4.0
systemd: through 239

References

http://www.securityfocus.com/bid/105747
https://access.redhat.com/errata/RHSA-2019:2091
https://access.redhat.com/errata/RHSA-2019:3222
https://access.redhat.com/errata/RHSA-2020:0593
https://github.com/systemd/systemd/pull/10519
https://lists.apache.org/thread.html/r1b103833cb5bc8466e24ff0ecc5e75b45a705334ab6a444e64e840a0%40%3Cissues.bookkeeper.apache.org%3E
https://lists.debian.org/debian-lts-announce/2018/11/msg00017.html
https://security.gentoo.org/glsa/201810-10
https://usn.ubuntu.com/3816-1/
https://www.exploit-db.com/exploits/45714/
https://www.oracle.com//security-alerts/cpujul2021.html
http://www.securityfocus.com/bid/105747

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