Connect with us

Hi, what are you looking for?

SecurityWeekSecurityWeek

Application Security

Cisco Patches High-Severity Security Flaws in IOS XR

Cisco this week released patches for multiple high-severity vulnerabilities in the IOS XR software and warned that attackers could exploit these bugs to reboot devices, elevate privileges, or overwrite and read arbitrary files.

Cisco this week released patches for multiple high-severity vulnerabilities in the IOS XR software and warned that attackers could exploit these bugs to reboot devices, elevate privileges, or overwrite and read arbitrary files.

The most severe of these issues is CVE-2021-34720 (CVSS score 8.6), a bug that could be exploited remotely without authentication to exhaust device packet memory, leading to a denial of service (DoS) condition.

The issue was identified in the IP Service Level Agreements (IP SLA) responder and Two-Way Active Measurement Protocol (TWAMP) features of IOS XR and exists because socket creation failures are not handled correctly during the IP SLA and TWAMP processes.

By sending specific IP SLA or TWAMP packets, an attacker could trigger the vulnerability to exhaust the packet memory. This could result in the crash of the IP SLA process or could affect other processes, such as routing protocols.

Cisco also patched a separate issue (CVE-2021-34718, CVSS 8.1) in the SSH Server process of IOS XR that could be exploited by a remote attacker to overwrite and read arbitrary files. Exploitation of this bug requires authentication.

[ READ: Microsoft Warns of Information Leak Flaw in Azure Container Instances ]

The issue exists because arguments that the user supplies for a specific file transfer method aren’t sufficiently validated. Thus, a low-privileged attacker could specify Secure Copy Protocol (SCP) parameters at authentication, which could allow them to elevate privileges and retrieve and upload files on a device.

Two other high severity privilege escalation bugs (CVE-2021-34719 and CVE-2021-34728) were also addressed in IOS XR, along with a denial of service flaw (CVE-2021-34713) affecting ASR 9000 series aggregation services routers that could lead to line card reboots.

Advertisement. Scroll to continue reading.

Software updates were released to address all of these vulnerabilities and Cisco says it is not aware of any public exploits or malicious attacks targeting them.

Seven other security bugs were addressed in IOS XR software this week, all rated medium severity. Cisco included all of these vulnerabilities in its September 2021 semi-annual bundle of IOS XR Software security advisories.

In a separate advisory on Thursday, the U.S. government’s Cybersecurity and Infrastructure Security Agency (CISA) urged organizations to apply the Cisco patches as soon as possible.

“An attacker could exploit some of these vulnerabilities to take control of an affected system. […]CISA encourages users and administrators to review the […] Cisco advisories and apply the necessary updates,” CISA said.

Related: Cisco Patches Critical Enterprise NFVIS Vulnerability

Related: Cisco Patches Serious Vulnerabilities in Data Center Products

Written By

Ionut Arghire is an international correspondent for SecurityWeek.

Click to comment

Trending

Daily Briefing Newsletter

Subscribe to the SecurityWeek Email Briefing to stay informed on the latest threats, trends, and technology, along with insightful columns from industry experts.

Understand how to go beyond effectively communicating new security strategies and recommendations.

Register

Join us for an in depth exploration of the critical nature of software and vendor supply chain security issues with a focus on understanding how attacks against identity infrastructure come with major cascading effects.

Register

Expert Insights

Related Content

Application Security

Cycode, a startup that provides solutions for protecting software source code, emerged from stealth mode on Tuesday with $4.6 million in seed funding.

Vulnerabilities

Less than a week after announcing that it would suspended service indefinitely due to a conflict with an (at the time) unnamed security researcher...

Cybercrime

The changing nature of what we still generally call ransomware will continue through 2023, driven by three primary conditions.

Data Protection

The cryptopocalypse is the point at which quantum computing becomes powerful enough to use Shor’s algorithm to crack PKI encryption.

Cybercrime

A recently disclosed vBulletin vulnerability, which had a zero-day status for roughly two days last week, was exploited in a hacker attack targeting the...

Identity & Access

Zero trust is not a replacement for identity and access management (IAM), but is the extension of IAM principles from people to everyone and...

Data Breaches

OpenAI has confirmed a ChatGPT data breach on the same day a security firm reported seeing the use of a component affected by an...