PostgreSQL observable response discrepancy with non-default scram_iterations provides user existence oracle

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Information Exposure

Overview Affected versions of this package are vulnerable to Information Exposure via the authentication process. An attacker can determine whether a specific user exists by observing differences in the SCRAM authentication challenge when the targeted user has a non-default scramiterations value...

AZL-95702 CVE-2026-14672 affecting package postgresql for versions less than 16.15-1

Observable response discrepancy in PostgreSQL SCRAM authentication allows an unauthenticated user to test the existence of a user via observing the SCRAM iteration count. This requires the probed user to have a non-default scramiterations count, because the authentication challenge for a...