SB2021031560 - Ubuntu update for xrdp
Published: March 15, 2021 Updated: October 31, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 2 vulnerabilities.
1) Buffer overflow (CVE-ID: CVE-2017-16927)
CWE-ID: CWE-119 - Memory corruption
CVSSv4: 8.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote non-authenticated attacker to execute arbitrary code.
The scp_v0s_accept function in sesman/libscp/libscp_v0.c in the session manager in xrdp through 0.9.4 uses an untrusted integer as a write length, which allows local users to cause a denial of service (buffer overflow and application crash) or possibly have unspecified other impact via a crafted input stream.
2) Improper Authentication (CVE-ID: CVE-2017-6967)
CWE-ID: CWE-287 - Improper Authentication
CVSSv4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N]
The vulnerability allows a remote non-authenticated attacker to read and manipulate data.
xrdp 0.9.1 calls the PAM function auth_start_session() in an incorrect location, leading to PAM session modules not being properly initialized, with a potential consequence of incorrect configurations or elevation of privileges, aka a pam_limits.so bypass.
Remediation
Install update from vendor's website.