SB2017092403 - Multiple vulnerabilities in MIT Kerberos

Description

This security bulletin contains information about 2 vulnerabilities.

1) Double free error (CVE-ID: CVE-2017-11462)

CWE-ID: CWE-415 - Double Free

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber

The vulnerability allows a remote attacker to cause DoS condition or execute arbitrary code on the target system.

The weakness exists due to double free during the automatic deletion of security contexts on error by the GSS-API. A remote attacker can delete an existing security context on a second or subsequent call to gss_init_sec_context() or gss_accept_sec_context(), trigger memory corruption and cause denial of service or execute arbitrary code.

2) Denial of service (CVE-ID: CVE-2017-11368)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear

The vulnerability allows a remote authenticated attacker to cause DoS condition on the target system.

The weakness exists due to an assertion failure. A remote attacker can send invalid S4U2Self or S4U2Proxy requests and cause the krb5kdc service to exit on a targeted system.

Successful exploitation of the vulnerability results in denial of service.

Remediation

Install update from vendor's website.

References

• http://krbdev.mit.edu/rt/Ticket/Display.html?id=8598
• http://krbdev.mit.edu/rt/Ticket/Display.html?id=8599