CVE-2017-12333 - Improper Verification of Cryptographic Signature

Severity

46%

Complexity

39%

Confidentiality

106%

A vulnerability in Cisco NX-OS System Software could allow an authenticated, local attacker to bypass signature verification when loading a software image. The vulnerability is due to insufficient NX-OS signature verification for software images. An authenticated, local attacker could exploit this vulnerability to bypass signature verification and load a crafted, unsigned software image on a targeted device. The attacker would need valid administrator credentials to perform this exploit. This vulnerability affects the following products running Cisco NX-OS System Software: Multilayer Director Switches, Nexus 7000 Series Switches, Nexus 7700 Series Switches, Unified Computing System Manager. Cisco Bug IDs: CSCvf25045, CSCvf31495.

A vulnerability in Cisco NX-OS System Software could allow an authenticated, local attacker to bypass signature verification when loading a software image. The vulnerability is due to insufficient NX-OS signature verification for software images. An authenticated, local attacker could exploit this vulnerability to bypass signature verification and load a crafted, unsigned software image on a targeted device. The attacker would need valid administrator credentials to perform this exploit. This vulnerability affects the following products running Cisco NX-OS System Software: Multilayer Director Switches, Nexus 7000 Series Switches, Nexus 7700 Series Switches, Unified Computing System Manager. Cisco Bug IDs: CSCvf25045, CSCvf31495.

CVSS 3.0 Base Score 6.7. CVSS Attack Vector: local. CVSS Attack Complexity: low. CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H).

CVSS 2.0 Base Score 4.6. CVSS Attack Vector: local. CVSS Attack Complexity: low. CVSS Vector: (AV:L/AC:L/Au:N/C:P/I:P/A:P).

Demo Examples

Improper Verification of Cryptographic Signature

CWE-347

In the following code, a JarFile object is created from a downloaded file.


               
JarFile jf = new JarFile(f);

The JAR file that was potentially downloaded from an untrusted source is created without verifying the signature (if present). An alternate constructor that accepts a boolean verify parameter should be used instead.

Overview

First reported 7 years ago

2017-11-30 09:29:00

Last updated 7 years ago

2017-12-15 02:29:00

Affected Software

Cisco NX-OS 8.1(1)

8.1\(1\)

References

102161

1039933

Third Party Advisory, VDB Entry

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20171129-nxos2

Vendor Advisory

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