CVE-2026-73108

Description

RustDesk versions before 1.4.7 contain an uncontrolled speculative memory allocation vulnerability in BytesCodec. Before authentication, the decoder trusts the payload length encoded in a four-byte frame header and reserves that amount before receiving the payload. A crafted header can request up to 1,073,741,823 bytes of capacity, allowing unauthenticated attackers to use concurrent TCP connections to cause memory exhaustion and denial of service. The fix caps header-triggered speculative preallocation at 256 KiB.

References

• https://github.com/rustdesk/hbb_common/commit/547da54b4ee58eed47163fbd47edb4639e3d88de
• https://github.com/rustdesk/rustdesk/commit/518296f2570d107ad416f29ade5fcce3177f4115
• https://github.com/rustdesk/rustdesk/releases/tag/1.4.7
• https://www.vulncheck.com/advisories/rustdesk-uncontrolled-memory-allocation-dos-via-bytescodec