Cisco has patched a bug in Unified Communications Manager that lets an unauthenticated attacker on the network write files to the box and, from there, climb to root.
It is tracked as CVE-2026-20230, and proof-of-concept exploit code is already public. Cisco’s PSIRT says it has not seen the flaw used in attacks yet. The PoC shortens that runway.
The flaw is a server-side request forgery.