CVE-2023-7256: libpcap Double Free — Fix

Description

In affected libpcap versions during the setup of a remote packet capture the internal function sock_initaddress() calls getaddrinfo() and possibly freeaddrinfo(), but does not clearly indicate to the caller function whether freeaddrinfo() still remains to be called after the function returns. This makes it possible in some scenarios that both the function and its caller call freeaddrinfo() for the same allocated memory block. A similar problem was reported in Apple libpcap, to which Apple assigned CVE-2023-40400.

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CVSS v3.1 Score

4.4

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-415 CWE-415

Affected Products

Vendor	Product	Versions
tcpdump	libpcap	< 1.10.5

References

Advisories & Patches

https://github.com/the-tcpdump-group/libpcap/commit/262e4f34979872d822ccedf9f318ed89c4d31c03 https://github.com/the-tcpdump-group/libpcap/commit/2aa69b04d8173b18a0e3492e0c8f2f7fabdf642d

Frequently Asked Questions

What is CVE-2023-7256? +

In affected libpcap versions during the setup of a remote packet capture the internal function sock_initaddress() calls getaddrinfo() and possibly freeaddrinfo(), but does not clearly indicate to the caller function whether freeaddrinfo() still remains to be called after the function returns. This makes it possible in some scenarios that both the function and its caller call freeaddrinfo() for the same allocated memory block. A similar problem was reported in Apple libpcap, to which Apple assigned CVE-2023-40400. It has a CVSS v3.1 base score of 4.4 (MEDIUM).

How severe is CVE-2023-7256? +

CVE-2023-7256 has a CVSS v3.1 score of 4.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2023-7256? +

CVE-2023-7256 affects products from tcpdump, specifically: libpcap. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-7256? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2023-7256