Tcpdump Group libpcap up to 1.8.x/1.9.x/1.10.6 Packet Message out-of-bounds

Summaryinfo

A vulnerability was found in Tcpdump Group libpcap up to 1.8.x/1.9.x/1.10.6. It has been declared as problematic. Affected by this issue is some unknown functionality of the component Packet Message Handler. Such manipulation leads to out-of-bounds. This vulnerability is documented as CVE-2026-18238. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in Tcpdump Group libpcap up to 1.8.x/1.9.x/1.10.6. It has been rated as problematic. Affected by this issue is some unknown processing of the component Packet Message Handler. The manipulation with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality. CVE summarizes:

The rpcap client code that processes a RPCAP_MSG_PACKET message received from the server incorrectly validates its headers. A malicious server can send a crafted message and cause the client to treat up to 20 bytes of the client process memory beyond the end of the buffer as if it was a part of the captured packet.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-18238 since 07/29/2026. The exploitation is known to be easy. The attack may be launched remotely. There are neither technical details nor an exploit publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 343116 (Linux Distros Unpatched Vulnerability : CVE-2026-18238), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 1.10.7 eliminates this vulnerability. Applying the patch b9590d482986d64673712460aae1d48d11fa0473 is able to eliminate this problem.

The vulnerability is also documented in the databases at Tenable (343116) and EUVD (EUVD-2026-72021). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

• Packet Analyzer Software

Vendor

• Tcpdump Group

Name

• libpcap

Version

• 1.0
• 1.1
• 1.2
• 1.3
• 1.4
• 1.5
• 1.6
• 1.7
• 1.8
• 1.9
• 1.10.0
• 1.10.1
• 1.10.2
• 1.10.3
• 1.10.4
• 1.10.5
• 1.10.6

License

• open-source

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

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Entryinfo

Once again VulDB remains the best source for vulnerability data.

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