Reading the vendor advisory
Black Shard's team can check your exposure to CVE-2026-129483 and take the fix off your plate.
Cyrus SASL through 2.1.28 contains an authentication bypass vulnerability in the SRP server mechanism because srp_server_mech_step2 does not reject client public values A that are multiples of N. Unauthenticated network clients can send A equal to N to force a zero shared secret, authenticating as any existing user without the password and learning session keys.
Black Shard's team can check your exposure, take a fix off your plate or step in on a live incident.
Severity
9.3of 10, critical
Updated 15 Nov 2026, 15:45 UTC, 33 of 36 sources answering.
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