Enterprise Defenses Strong at Perimeter, Weak Inside: Picus 2026

Enterprise defenses are having one of their strongest years on record at the network perimeter, but collapse almost entirely once an attacker is inside. According to Picus Labs' newly released Blue Report 2026, which analyzed more than 338 million real attack simulations against live client production environments in the first half of 2026, average prevention effectiveness climbed from 62% to 69%, matching its 2024 peak, while logging reached a four-year high of 58%. The recovery is real, but it lives almost entirely at the edge.

The report's sharper finding concerns what happens after the perimeter is breached. For the first time, Picus Labs measured post-compromise prevention using autonomous penetration testing, simulating what controls actually break the attack chain once an adversary is operating inside the network as an authenticated user. The Post-Compromise Prevention Rate came in at just 37%. Noisy post-exploitation actions were caught reliably, with years of assume-breach EDR investment paying off as expected: lateral movement via service execution techniques such as Sharp-ServiceExec and SMBExec was stopped roughly 90% of the time, and UAC-bypass privilege escalation was blocked around 85%.

The interior does not fail evenly, however. It fails along a single, clean line that separates loud from quiet techniques. Reconnaissance, the mapping of domains, enumeration of shares, and listing of sessions, was the least-prevented category of all, stopped a paltry 10% of the time. Credential theft from memory fared slightly better at around 22%, but one variant, pulling secrets straight from the registry, was blocked in less than 1% of attempts. A particularly telling test ran the same credential-theft tool, Mimikatz, against three identical objectives: dumping credentials the heavily signatured way from LSASS process memory was blocked almost every time, while pulling them from alternative memory locations slipped through, exposing how signature-based controls miss the behavior they are meant to catch. Such silent credential harvesting is precisely why individuals should routinely verify their own credentials with a password checker and confirm whether any accounts have surfaced in a known compromise using a breach checker.

The implication for defenders is that assume-breach has effectively become assume-reconnaissance. Attackers can map the environment, harvest sessions, and read credential material with almost no resistance, getting their bearings before triggering any action noisy enough to trip an EDR. That makes hardening the inside of the network against silent activity, particularly credential exposure and the kind of share and service enumeration that a basic port scanner reveals in seconds, as urgent as any zero-day patch, and it makes disciplined credential hygiene the difference between catching an attack and merely logging its aftermath.