Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability
Multiple vulnerabilities in the Distance Vector Multicast Routing Protocol (DVMRP) feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to either immediately crash the Internet Group Management Protocol (IGMP)…
Severity = CVSS. Probability = EPSS (FIRST). Exploitation = public signals: KEV, EUVD, ransomware, EPSS above 10 %, no account required.
Exploitation probability EPSS · FIRST
Exploitation signals 3 / 5
- KEV catalog (CISA)03 Nov 2021
- Exploited in EUVD (ENISA)03 Nov 2021
- Used by ransomwareno
- EPSS above 10 %3.3%
- No account, over the networkyes
What to do
Fix
Apply the vendor’s fix as soon as it is available.
CISA guidance: Apply updates per vendor instructions.
Meanwhile
Take the service off the internet or restrict access to it, watch the logs and look for signs of compromise.
Manufacturers (CRA)
Exploited vulnerability in your product: early warning to ENISA within 24 h, then notification within 72 h (Article 14 of the Cyber Resilience Act). The CRA explained
Description ENISA EUVD
Multiple vulnerabilities in the Distance Vector Multicast Routing Protocol (DVMRP) feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to either immediately crash the Internet Group Management Protocol (IGMP) process or make it consume available memory and eventually crash. The memory consumption may negatively impact other processes that are running on the device. These vulnerabilities are due to the incorrect handling of IGMP packets. An attacker could exploit these vulnerabilities by sending crafted IGMP traffic to an affected device. A successful exploit could allow the attacker to immediately crash the IGMP process or cause memory exhaustion, resulting in other processes becoming unstable. These processes may include, but are not limited to, interior and exterior routing protocols. Cisco will release software updates that address these vulnerabilities.
Affected products
Open source packages OSV
Affected libraries according to OSV, with fixed versions.
Timeline
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Published
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Exploitation reported (ENISA)
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Added to the KEV catalog
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CISA remediation due date
References
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