Buffer overflow in The Tcpdump Group Libpcap

CVE-2025-11961

pcap_ether_aton() is an auxiliary function in libpcap, it takes a string argument and returns a fixed-size allocated buffer. The string argument must be a well-formed MAC-48 address in one of the supported formats, but this requirement has been poorly documented. If an application calls the function with an argument that deviates from the expected format, the function can read data beyond the end of the provided string and write data beyond the end of the allocated buffer.

Vulnerability class: Buffer Overflow

EPSS: 0.001 (0.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 1.9 (Low). Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:L/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-11961?
CVE-2025-11961 is a low-severity vulnerability in The Tcpdump Group Libpcap, classified under Heap-based Buffer Overflow. CVSS score: 1.9/10. Published 2025-12-31.
How severe is CVE-2025-11961?
Low severity. CVSS v3 base score is 1.9 out of 10.