CVE-2022-26127 in FRRouting
Summary
by MITRE • 03/03/2022
A buffer overflow vulnerability exists in FRRouting through 8.1.0 due to missing a check on the input packet length in the babel_packet_examin function in babeld/message.c.
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Analysis
by VulDB Data Team • 11/05/2025
The buffer overflow vulnerability identified as CVE-2022-26127 affects FRRouting versions through 8.1.0 and represents a critical security flaw within the Babel routing protocol implementation. This vulnerability stems from inadequate input validation within the babel_packet_examin function located in babeld/message.c, where the software fails to properly verify packet length constraints before processing incoming network data. The absence of proper bounds checking creates an exploitable condition that can be leveraged by remote attackers to manipulate memory structures and potentially execute arbitrary code.
The technical nature of this vulnerability aligns with CWE-121, which describes buffer overflow conditions where insufficient checks on input data length allow attackers to write beyond allocated memory boundaries. The flaw specifically manifests when the babel_packet_examin function processes incoming Babel protocol packets without validating whether the packet size exceeds expected parameters, creating opportunities for stack-based or heap-based buffer overflows depending on the memory layout. This type of vulnerability falls under the ATT&CK technique T1190, which involves exploitation of vulnerabilities in network protocols to achieve remote code execution or denial of service conditions.
The operational impact of this vulnerability extends beyond simple exploitation as it affects the stability and security of routing infrastructure that relies on FRRouting for Babel protocol implementation. Network devices running affected versions could experience denial of service conditions when processing malformed packets, potentially causing routing protocol failures and network disruption. Additionally, successful exploitation could enable attackers to execute arbitrary code with the privileges of the routing daemon process, potentially leading to complete system compromise or lateral movement within the network infrastructure. The vulnerability affects implementations where Babel routing protocol is enabled, making it particularly concerning for network devices that serve as routing nodes in complex network topologies.
Mitigation strategies for CVE-2022-26127 should prioritize immediate patching of affected FRRouting installations to version 8.1.1 or later, where the input validation has been corrected to properly check packet lengths before processing. Network administrators should implement additional defensive measures including packet filtering rules that limit Babel protocol traffic to trusted sources, monitoring for anomalous packet sizes, and implementing intrusion detection systems that can identify potential exploitation attempts. The fix typically involves adding proper length validation checks within the babel_packet_examin function to ensure that incoming packets conform to expected size parameters before any processing occurs. Organizations should also consider network segmentation to limit the potential impact of successful exploitation and implement regular security assessments to identify similar vulnerabilities in other routing protocol implementations.