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downgrade attack

Tricking a device into installing an older, genuinely signed release that has a known hole.

A downgrade attack offers an authentic but older firmware with a known vulnerability; signatures alone don't stop it, a version check or anti-rollback counter does.

Examples

  • An attacker re-offers the genuine, signed 1.4.0 to a fan controller already on 1.5.0, hoping to bring back a hole that 1.5.0 fixed.

  • The signature check passes on an old release, which is why a version check, and in hardware an anti-rollback counter, are needed too.

See also

anti-rollback counter update manifest digital signature
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