CVE-2017-3145 in BIND
Summary
by MITRE
BIND was improperly sequencing cleanup operations on upstream recursion fetch contexts, leading in some cases to a use-after-free error that can trigger an assertion failure and crash in named. Affects BIND 9.0.0 to 9.8.x, 9.9.0 to 9.9.11, 9.10.0 to 9.10.6, 9.11.0 to 9.11.2, 9.9.3-S1 to 9.9.11-S1, 9.10.5-S1 to 9.10.6-S1, 9.12.0a1 to 9.12.0rc1.
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Analysis
by VulDB Data Team • 07/01/2023
The vulnerability identified as CVE-2017-3145 affects the Berkeley Internet Name Domain (BIND) software, specifically impacting versions ranging from 9.0.0 through 9.8.x, 9.9.0 through 9.9.11, 9.10.0 through 9.10.6, 9.11.0 through 9.11.2, and several snapshot versions within these ranges. This issue represents a critical flaw in the recursive DNS resolution process that can lead to system instability and potential denial of service conditions. The vulnerability manifests when BIND improperly sequences cleanup operations during upstream recursion fetch contexts, creating a scenario where memory management becomes inconsistent and potentially exploitable.
The technical root cause of this vulnerability lies in the improper handling of memory cleanup operations within the recursive query processing pipeline. When BIND processes recursive DNS queries, it maintains context structures that track the state of upstream fetch operations. The flaw occurs when these cleanup operations are executed in an incorrect order, leading to situations where memory allocated for these contexts may be freed while still being referenced by other processes or threads. This use-after-free condition creates a scenario where the application attempts to access memory that has already been deallocated, resulting in unpredictable behavior and system crashes.
The operational impact of CVE-2017-3145 extends beyond simple service disruption to potentially enable more sophisticated attacks. When the use-after-free condition triggers an assertion failure in the named process, it causes the DNS server to crash and restart, effectively creating a denial of service condition that can persist until manual intervention occurs. This vulnerability is particularly concerning in environments where DNS servers are critical infrastructure components, as it can lead to widespread service interruptions. The attack surface is broad since any DNS server running affected versions could be exploited, making this a significant concern for organizations relying on BIND for their DNS infrastructure.
Security researchers have classified this vulnerability under CWE-416, which describes the use of freed memory condition, and it aligns with ATT&CK technique T1499.004, which covers network denial of service attacks. The vulnerability demonstrates a classic memory safety issue where improper resource management leads to system instability. Organizations running affected BIND versions should immediately implement mitigations including upgrading to patched versions, as the vulnerability can potentially be exploited by remote attackers to cause system crashes or, in more sophisticated scenarios, could potentially lead to arbitrary code execution depending on the specific implementation details and system configurations.
The remediation strategy for CVE-2017-3145 requires immediate deployment of updated BIND versions that contain proper cleanup sequencing logic. System administrators should prioritize patching across all DNS infrastructure, particularly authoritative and recursive servers that handle high volumes of queries. Additionally, monitoring systems should be configured to detect unusual crash patterns or restart events that might indicate exploitation attempts. Network segmentation and access controls should be reviewed to limit exposure, while implementing proper logging and alerting mechanisms to detect potential abuse of this vulnerability in production environments. The vulnerability underscores the importance of proper memory management practices in server applications and highlights the critical need for regular security updates in DNS infrastructure components.