CVE-2011-3325 in Quagga
Summary
by MITRE
ospf_packet.c in ospfd in Quagga before 0.99.19 allows remote attackers to cause a denial of service (daemon crash) via (1) a 0x0a type field in an IPv4 packet header or (2) a truncated IPv4 Hello packet.
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Analysis
by VulDB Data Team • 12/23/2024
The vulnerability described in CVE-2011-3325 affects the ospfd daemon within the Quagga routing software suite, specifically targeting the OSPF (Open Shortest Path First) protocol implementation. This issue represents a critical denial of service vulnerability that can be exploited by remote attackers to crash the routing daemon, thereby disrupting network connectivity and potentially causing cascading failures in routed networks. The vulnerability exists in the ospf_packet.c file which handles packet processing for OSPF protocol messages, making it a fundamental component in the routing protocol stack.
The technical flaw manifests through two distinct attack vectors that exploit improper input validation within the OSPF packet processing logic. The first vector involves manipulation of the IPv4 packet header type field to a value of 0x0a, which triggers an unhandled condition in the packet parsing routine. The second vector exploits truncated IPv4 Hello packets where the packet length is insufficient to contain the expected OSPF header structure, causing memory access violations or buffer overflows during packet processing. Both attack scenarios result in the ospfd daemon crashing due to lack of proper error handling and validation mechanisms, which is classified under CWE-129 as Improper Validation of Array Index and CWE-248 as Uncaught Exception.
The operational impact of this vulnerability extends beyond simple service disruption as it affects the stability and reliability of routing infrastructure. When the ospfd daemon crashes, it can cause routing table inconsistencies, temporary network outages, and require manual intervention to restore normal operations. Network administrators must perform restart procedures that may result in routing convergence delays, potentially affecting network performance and availability. This vulnerability is particularly dangerous in production environments where routing stability is paramount, as it can be exploited by malicious actors to create network disruptions or as part of larger attack campaigns targeting infrastructure availability.
Mitigation strategies should focus on immediate patch deployment to Quagga versions 0.99.19 or later where the vulnerability has been addressed through proper input validation and error handling. Network administrators should also implement monitoring solutions to detect unusual packet patterns that might indicate exploitation attempts. The fix typically involves adding proper bounds checking for packet headers and implementing graceful error handling for malformed packets rather than allowing the daemon to crash. Additionally, network segmentation and access controls can limit the attack surface by restricting direct access to OSPF routing daemons from untrusted networks, aligning with ATT&CK technique T1498 for Network Denial of Service and T1562.001 for Impairing Availability through resource exhaustion. Organizations should also consider implementing intrusion detection systems capable of identifying and alerting on suspicious OSPF packet structures that match the vulnerability patterns described in the CVE.