CVE-2012-6056 in Wireshark
Summary
by MITRE
Integer overflow in the dissect_sack_chunk function in epan/dissectors/packet-sctp.c in the SCTP dissector in Wireshark 1.8.x before 1.8.4 allows remote attackers to cause a denial of service (infinite loop) via a crafted Duplicate TSN count.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 12/20/2021
The vulnerability identified as CVE-2012-6056 represents a critical integer overflow flaw within the SCTP dissector component of Wireshark version 1.8.x prior to 1.8.4. This issue manifests in the dissect_sack_chunk function located in epan/dissectors/packet-sctp.c, where improper handling of the Duplicate TSN count field creates a condition that can be exploited by remote attackers to trigger a denial of service scenario. The flaw specifically occurs when processing SCTP (Stream Control Transmission Protocol) packets during network traffic analysis, making it particularly dangerous in environments where network monitoring and packet inspection are critical operations.
The technical implementation of this vulnerability stems from an insufficient validation of input parameters within the SCTP chunk processing logic. When a crafted packet containing an oversized Duplicate TSN count value is processed by Wireshark's dissector, the integer overflow causes the loop counter to wrap around to a very large positive value or zero, resulting in an infinite loop during packet analysis. This occurs because the dissector fails to properly validate that the Duplicate TSN count parameter remains within acceptable bounds before using it to control loop iterations. The vulnerability aligns with CWE-190, which specifically addresses integer overflow conditions, and demonstrates how improper input validation can lead to denial of service conditions in network protocol analysis tools.
The operational impact of this vulnerability extends beyond simple service disruption, as it affects the reliability and availability of network monitoring infrastructure that relies on Wireshark for packet analysis. Attackers can exploit this weakness by crafting malicious SCTP packets that, when captured and analyzed by vulnerable Wireshark instances, cause the application to enter an infinite loop consuming excessive CPU resources. This denial of service condition can render network troubleshooting and monitoring capabilities ineffective, potentially masking actual network issues while the analysis tool becomes unresponsive. The vulnerability affects any system running affected Wireshark versions and can be particularly problematic in environments where continuous network monitoring is required, such as security operations centers or network infrastructure monitoring systems.
Mitigation strategies for CVE-2012-6056 primarily involve immediate patching of affected Wireshark installations to version 1.8.4 or later, which contains the necessary fixes to properly validate the Duplicate TSN count parameter. Network administrators should also implement network segmentation and monitoring to detect anomalous SCTP traffic patterns that might indicate exploitation attempts. Additionally, organizations can consider implementing network access controls to limit exposure to potentially malicious SCTP traffic, though this approach provides only partial protection since the vulnerability can be triggered through legitimate network traffic analysis. The fix implemented in the patched versions typically involves adding proper bounds checking to ensure that the Duplicate TSN count parameter cannot cause integer overflow conditions during loop execution, directly addressing the root cause identified in the ATT&CK framework under the T1499.004 technique for network denial of service.