Description
rdesktop through 1.9.0 contains a heap out-of-bounds read vulnerability in process_bmpcache2() in orders.c that allows malicious RDP servers to crash clients via crafted revision-2 bitmap cache orders. Attackers can send an uncompressed order with large width/height or an underflowing mode nibble and short payload, causing memcpy() reads past the receive buffer and denial of service.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| rdesktop | rdesktop | ≤ 1.9.0 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | rdesktop | No fix yet | — |
| Debian 13 | rdesktop | No fix yet | — |
| Debian 12 | rdesktop | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | rdesktop | No fix yet | — |
| Ubuntu 26.04 LTS | rdesktop | No fix yet | — |
| Ubuntu 24.04 LTS | rdesktop | No fix yet | — |
| Ubuntu 22.04 LTS | rdesktop | No fix yet | — |
| Ubuntu 20.04 LTS | rdesktop | No fix yet | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | rdesktop | No fix yet | — |
| Ubuntu 16.04 LTS | rdesktop | No fix yet | — |
References
- https://hackmd.io/@haindpwn/rdesktop-bitmap-decompress-oob-read third-party-advisory
- https://github.com/rdesktop/rdesktop/issues/436 issue-tracking
- https://github.com/rdesktop/rdesktop/pull/437 patch issue-tracking
- https://github.com/rdesktop/rdesktop/blob/v1.9.0/orders.c technical-description
- VulnCheck Advisory: rdesktop through 1.9.0 Heap Out-of-Bounds Read via process_bmpcache2 third-party-advisory