CVE-2015-8677 in S5300EI
Summary
by MITRE
Memory leak in Huawei S5300EI, S5300SI, S5310HI, and S6300EI Campus series switches with software V200R003C00 before V200R003SPH011 and V200R005C00 before V200R005SPH008; S2350EI and S5300LI Campus series switches with software V200R003C00 before V200R003SPH011, V200R005C00 before V200R005SPH008, and V200R006C00 before V200R006SPH002; S9300, S7700, and S9700 Campus series switches with software V200R003C00 before V200R003SPH011, V200R005C00 before V200R005SPH009, and V200R006C00 before V200R006SPH003; S5720HI and S5720EI Campus series switches with software V200R006C00 before V200R006SPH002; and S2300 and S3300 Campus series switches with software V100R006C05 before V100R006SPH022 allows remote authenticated users to cause a denial of service (memory consumption and device restart) by logging in and out of the (1) HTTPS or (2) SFTP server, related to SSL session information.
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Analysis
by VulDB Data Team • 07/24/2022
The vulnerability identified as CVE-2015-8677 represents a critical memory leak issue affecting multiple Huawei Campus series network switches including S5300EI, S5300SI, S5310HI, S6300EI, S2350EI, S5300LI, S9300, S7700, S9700, S5720HI, S5720EI, S2300, and S3300 models. This flaw specifically targets the SSL session management functionality within these network devices, creating a persistent memory consumption problem that can ultimately lead to device instability and service disruption. The vulnerability exists in software versions prior to specific service pack releases, indicating a well-documented issue that Huawei addressed through targeted patches. The memory leak occurs during the authentication process when users interact with HTTPS or SFTP services, making it particularly dangerous as it can be exploited by authenticated attackers who already have access to the network infrastructure.
The technical mechanism behind this vulnerability involves improper handling of SSL session information within the switch's secure communication protocols. When authenticated users perform login and logout operations against the HTTPS or SFTP servers, the system fails to properly release memory allocated for SSL session contexts. This memory management failure results in gradual memory consumption over time, as each authentication cycle creates new session data without adequate cleanup of previous sessions. The vulnerability is classified under CWE-401 as a failure to release memory, which directly maps to the common security principle that improper resource management leads to system instability and potential denial of service conditions. The flaw is particularly insidious because it requires only authenticated access to the switch's management interfaces, making it exploitable by insiders or attackers who have gained legitimate credentials.
From an operational impact perspective, this vulnerability creates significant risk for network infrastructure reliability and availability. The gradual memory consumption can lead to complete device restarts or reboot cycles, disrupting network services and potentially causing cascading failures across the affected network segments. Network administrators may experience unexpected downtime, increased maintenance overhead, and potential service degradation as the devices approach memory exhaustion. The vulnerability affects critical network infrastructure components that typically operate continuously, making the impact on business operations particularly severe. Organizations relying on these switches for campus network connectivity face increased risk of service interruptions that could affect thousands of users simultaneously, especially during peak network usage periods when memory resources are already strained.
The exploitation of this vulnerability aligns with ATT&CK technique T1499.004 which involves network disruption through resource exhaustion, and T1566.001 which covers credential access through valid accounts. Attackers can leverage their authenticated access to repeatedly initiate SSL session creation and destruction cycles, causing progressive memory consumption until the device becomes unresponsive. This makes the vulnerability particularly dangerous in environments where network switches are critical to overall infrastructure stability. The impact extends beyond simple service disruption to potentially creating security gaps, as device reboots may temporarily disable network monitoring and logging capabilities. Organizations should implement immediate mitigation strategies including applying the relevant Huawei service packs, monitoring memory usage patterns on affected devices, and establishing alerting mechanisms to detect potential exploitation attempts. Additionally, network segmentation and access control measures should be reviewed to limit the potential impact of authenticated users who might exploit this vulnerability.