Juniper Networks Session Smart Router has an out-of-bounds read vulnerability in its VRRP implementation. A specially crafted VRRPv3 advertisement can trigger a read of stale memory contents or cause a system fault. The flaw represents a classic buffer overread (CWE‑125) that can expose sensitive data from memory or destabilize the device through an unintended crash.

The vulnerability affects Session Smart Router firmware versions before 7.0.5, before 7.1.7, and before 7.2.3. All releases 7.0.5 and higher, 7.1.7 and higher, and 7.2.3 and higher contain the necessary fix, as identified by the vendor.

The CVSS score of 4.3 indicates a moderate impact. EPSS data is not available, and the vulnerability is not listed in the CISA KEV catalog, so it has no known public exploits at the time of this analysis. Based on the description, the likely attack vector is a Layer‑2 adjacent attacker delivering a crafted VRRPv3 packet to the router, which is able to read memory or trigger a crash. The risk to affected deployments is therefore moderate, limited to environments where untrusted devices can coexist on the same LAN segment.