Denial of serivce when handling DECnet traffic in Cisco IOS XE

1) Use of Out-of-range Pointer Offset

EUVDB-ID: #VU51708

Risk: Medium

CVSSv3.1: 5.7 [CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-1352

CWE-ID: CWE-823 - Use of Out-of-range Pointer Offset

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to improper input validation within the DECnet Phase IV and DECnet/OSI protocol. A remote attacker on the local network can send specially crafted DECnet traffic to the affected device and perform a denial of service (DoS) attack.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Cisco 2600 Series Multiservice Platforms: All versions

Cisco ASR 1000 Series Aggregation Services Routers: All versions

Cisco Cloud Services Router 1000V Series: All versions

Cisco Catalyst 3850 Series Switches: All versions

Cisco Catalyst 3650 Series Switches: All versions

Cisco 4000 Series Integrated Services Routers: All versions

Cisco 1000 Series Integrated Services Routers: All versions

Cisco Catalyst 9300 Series Switches: All versions

Cisco Catalyst 9500 Series Switches: All versions

Cisco Catalyst 9400 Series Switches: All versions

Cisco 1100 Series Industrial Integrated Services Routers: All versions

Cisco Catalyst 9200 Series Switches: All versions

Cisco Embedded Services 3300 Series Switches: All versions

Cisco Catalyst IE3200 Rugged Series: All versions

Cisco Catalyst IE3300 Rugged Series: All versions

Cisco Catalyst IE3400 Rugged Series: All versions

Cisco Catalyst 9600 Series Switches: All versions

Cisco Catalyst 9800 Series Wireless Controllers: All versions

Cisco Catalyst IE3400 Heavy Duty Series: All versions

Cisco IOS XE: 16.12

External links

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-decnet-dos-cuPWDkyL
http://bst.cloudapps.cisco.com/bugsearch/bug/CSCvv51476

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected device in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.