CVE-2026-73108
RustDesk versions before 1.4.7 contain an uncontrolled speculative memory allocation vulnerability in BytesCodec.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.53%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 4.0
- 8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.53% probability · 43th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-770
- Source
- disclosure@vulncheck.com
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
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.