CVE-2019-3844
개요
It was discovered that a systemd service that uses DynamicUser property can get new privileges through the execution of SUID binaries, which would allow a cooperating process to create binaries owned by the service transient group with the setgid bit set. A local attacker may use this flaw to access resources that will be owned by a potentially different service in the future when the GID will be recycled.
내용
This issue did not affect the versions of systemd as shipped with Red Hat Enterprise Linux 7 as they did not include support for DynamicUser property.
CVSS (Common Vulnerability Scoring System) 점수 세부 사항
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 점수 분석
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| 기본 점수 | 4.5 | 7.8 | N/A |
| 공격 벡터 | Local | Local | N/A |
| 공격 복잡성 | High | Low | N/A |
| 필요한 권한 | Low | Low | N/A |
| 사용자 상호 작용 | None | None | N/A |
| 범위 | Unchanged | Unchanged | N/A |
| 기밀성 | Low | High | N/A |
| 무결성에 미치는 영향 | Low | High | N/A |
| 가용성에 미치는 영향 | Low | High | N/A |
벡터
Red Hat: CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
취약점 이해 (CWE)
Access Control
Technical Impact: Gain Privileges or Assume Identity
A user can be given or gain access rights of another user. This can give the user unauthorized access to sensitive information including the access information of another user.
감사의 말
Red Hat would like to thank Jann Horn (Google Project Zero) for reporting this issue.
