Vulnerability · Published Jun 30, 2020 · Assigned by GitHub_M
CVE-2020-4044Local users can perform a buffer overflow attack against the xrdp-sesman service and then impersonate it
High 7.5
In plain English
A high-severity stack buffer overflow in xrdp from neutrinolabs. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 2.3% (higher than 84% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
The xrdp-sesman service before version 0.9.13.1 can be crashed by connecting over port 3350 and supplying a malicious payload. Once the xrdp-sesman process is dead, an unprivileged attacker on the server could then proceed to start their own imposter sesman service listening on port 3350. This will allow them to capture any user credentials that are submitted to XRDP and approve or reject arbitrary login credentials. For xorgxrdp sessions in particular, this allows an unauthorized user to hijack an existing session. This is a buffer overflow attack, so there may be a risk of arbitrary code execution as well.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.20 | xrdp | 0.9.13.1-r0 | ALPINE-CVE-2020-4044 |
| Alpine:v3.21 | xrdp | 0.9.13.1-r0 | ALPINE-CVE-2020-4044 |
| Alpine:v3.22 | xrdp | 0.9.13.1-r0 | ALPINE-CVE-2020-4044 |
| Alpine:v3.23 | xrdp | 0.9.13.1-r0 | ALPINE-CVE-2020-4044 |
| Alpine:v3.24 | xrdp | 0.9.13.1-r0 | ALPINE-CVE-2020-4044 |
| Debian:12 | xrdp | 0.9.12-1.1 | DEBIAN-CVE-2020-4044 |
| Debian:13 | xrdp | 0.9.12-1.1 | DEBIAN-CVE-2020-4044 |
| Debian:14 | xrdp | 0.9.12-1.1 | DEBIAN-CVE-2020-4044 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| neutrinolabs | xrdp | < 0.9.13.1 |
Weakness: CWE-121 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/neutrinolabs/xrdp/security/advisories/GHSA-j9fv-6fwf-p3g4 x_refsource_CONFIRM
- https://github.com/neutrinolabs/xrdp/releases/tag/v0.9.13.1 x_refsource_MISC
- https://github.com/neutrinolabs/xrdp/commit/0c791d073d0eb344ee7aaafd221513dc9226762c x_refsource_MISC
- openSUSE-SU-2020:0999 vendor-advisory, x_refsource_SUSE
- DSA-4737 vendor-advisory, x_refsource_DEBIAN
- [debian-lts-announce] 20200809 [SECURITY] [DLA 2319-1] xrdp security update mailing-list, x_refsource_MLIST
- openSUSE-SU-2020:1200 vendor-advisory, x_refsource_SUSE