# Firmware security-version state can be lowered

An attacker can reduce the protected security version and thereby restore software excluded by the anti-rollback policy.

**Candidate CWE:** [CWE-1328](https://cwe.mitre.org/data/definitions/1328.html)

## Test hypothesis

In a local model or recoverable bench fixture, compare an authentic current image and older signed security version. Trace whether the eligible caller can lower the counter or select a bypass path.

## Evidence required

Security counter before/after, downgrade policy, signed image versions, caller access and reinstated vulnerable security state.

## Rule out false positives

Normal application rollback after failed boot validation, lower marketing versions and explicitly permitted recovery are distinct from anti-rollback bypass.

## Playbook and command references

- [Firmware update and boot trust: signed bytes, product binding and rollback](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/modules/firmware-update.html) — Separate download trust, update authorization, image verification, rollback policy and boot enforcement using local artifacts.

[Find the associated command snippets](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/commands.html?q=Firmware%20update%20and%20boot%20trust%3A%20signed%20bytes%2C%20product%20binding%20and%20rollback)

## Referenced by these target playbooks

[Hardware & firmware](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/hardware.html) · [OSS & self-hosted](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/oss.html)

## Report checklist

- [ ] Capture the affected version, configuration, identities, and object ownership.
- [ ] Preserve a valid baseline and a negative control.
- [ ] Reproduce the forbidden data access, action, or state change on controlled fixtures.
- [ ] Explain the intended security rule and why the observed behavior violates it.
- [ ] State prerequisites, uncertainty, cleanup, and the smallest demonstrated impact.

## Conditional ATT&CK mapping

No direct ATT&CK mapping selected. Record the weakness and demonstrated impact without forcing an adversary-behavior classification. See the [mapping guide](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/attack.html).

## Primary references

- [CWE-1328: Security version mutable to older versions](https://cwe.mitre.org/data/definitions/1328.html)
- [Espressif OTA documentation](https://docs.espressif.com/projects/esp-idf/en/stable/esp32/api-reference/system/ota.html)

[Back to the complete vulnerability catalog](https://bug-bounty-field-manual.kmahshooq.chatgpt.site/vulnerabilities.html)