CVE-2019-19726

OpenBSD through 6.6 allows local users to escalate to root because a check for LD_LIBRARY_PATH in setuid programs can be defeated by setting a very small RLIMIT_DATA resource limit. When executing chpass or passwd (which are setuid root), _dl_setup_env in ld.so tries to strip LD_LIBRARY_PATH from the environment, but fails when it cannot allocate memory. Thus, the attacker is able to execute their own library code as root.

CVSS v3.0 7.8 HIGH
CVSS v2.0 7.2 HIGH

7.8^/10

CVSS v3.0 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

7.2^/10

CVSS v2.0 : HIGH

Vector : AV:L/AC:L/Au:N/C:C/I:C/A:C

Exploitability : 3.9 / Impact : 10.0

Access Vector LOCAL

Access Complexity LOW

Authentication NONE

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

References

Link	Resource
https://www.openbsd.org/errata66.html	Patch Vendor Advisory
https://www.openwall.com/lists/oss-security/2019/12/11/9	Mailing List Third Party Advisory
https://seclists.org/bugtraq/2019/Dec/25	Exploit Mailing List Third Party Advisory
http://packetstormsecurity.com/files/155658/Qualys-Security-Advisory-OpenBSD-Dynamic-Loader-Privilege-Escalation.html	Exploit Third Party Advisory VDB Entry
http://seclists.org/fulldisclosure/2019/Dec/31	Exploit Mailing List Third Party Advisory
http://packetstormsecurity.com/files/155764/OpenBSD-Dynamic-Loader-chpass-Privilege-Escalation.html	Third Party Advisory VDB Entry

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Configurations

Configuration 1 (hide)

cpe:2.3:o:openbsd:openbsd:*:*:*:*:*:*:*:*

Information

Published : 2019-12-11 17:15

Updated : 2023-01-30 12:00

NVD link : CVE-2019-19726

Mitre link : CVE-2019-19726

JSON object : View

CWE

CWE-269

Improper Privilege Management

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Products Affected

openbsd

openbsd

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