CVE-2023-40184
Improper handling of session establishment errors in xrdp
xrdp is an open source remote desktop protocol (RDP) server. In versions prior to 0.9.23 improper handling of session establishment errors allows bypassing OS-level session restrictions. The auth_start_session function can return non-zero (1) value on, e.g., PAM error which may result in in session restrictions such as max concurrent sessions per user by PAM (ex ./etc/security/limits.conf) to be bypassed. Users (administrators) don't use restrictions by PAM are not affected. This issue has been addressed in release version 0.9.23. Users are advised to upgrade. There are no known workarounds for this issue.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- Low
- User interaction
- Required
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
2.6
Improper handling of session establishment errors in xrdp
xrdp is an open source remote desktop protocol (RDP) server. In versions prior to 0.9.23 improper handling of session establishment errors allows bypassing OS-level session restrictions. The auth_start_session function can return non-zero (1) value on, e.g., PAM error which may result in in session restrictions such as max concurrent sessions per user by PAM (ex ./etc/security/limits.conf) to be bypassed. Users (administrators) don't use restrictions by PAM are not affected. This issue has been addressed in release version 0.9.23. Users are advised to upgrade. There are no known workarounds for this issue.
- Record
CVE-2023-40184- CVSS 3.1
- 2.6 Low
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:L - Weakness
- CWE-755
- Updated
- 2026-11-02
EUVDEUVD-2023-44784
2.6
xrdp is an open source remote desktop protocol (RDP) server. In versions prior to 0.9.23 improper handling of session establishment errors allows bypassing OS-level session restrictions. The auth_start_session function can return non-zero (1) value on, e.g., PAM error which may result in in session restrictions such as max concurrent sessions per user by PAM (ex ./etc/security/limits.conf) to be bypassed. Users (administrators) don't use restrictions by PAM are not affected. This issue has been addressed in release version 0.9.23. Users are advised to upgrade. There are no known workarounds for this issue.
- Record
EUVD-2023-44784- CVSS 3.1
- 2.6 Low
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:L - Updated
- 2026-11-02
NVD
2.6
xrdp is an open source remote desktop protocol (RDP) server. In versions prior to 0.9.23 improper handling of session establishment errors allows bypassing OS-level session restrictions. The auth_start_session function can return non-zero (1) value on, e.g., PAM error which may result in in session restrictions such as max concurrent sessions per user by PAM (ex ./etc/security/limits.conf) to be bypassed. Users (administrators) don't use restrictions by PAM are not affected. This issue has been addressed in release version 0.9.23. Users are advised to upgrade. There are no known workarounds for this issue.
- Record
CVE-2023-40184- CVSS 3.1
- 2.6 Low
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:L - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-755
- Updated
- 2026-11-02
OSVALPINE-CVE-2023-40184
6.5
xrdp is an open source remote desktop protocol (RDP) server. In versions prior to 0.9.23 improper handling of session establishment errors allows bypassing OS-level session restrictions. The auth_start_session function can return non-zero (1) value on, e.g., PAM error which may result in in session restrictions such as max concurrent sessions per user by PAM (ex ./etc/security/limits.conf) to be bypassed. Users (administrators) don't use restrictions by PAM are not affected. This issue has been addressed in release version 0.9.23. Users are advised to upgrade. There are no known workarounds for this issue.
- Record
ALPINE-CVE-2023-40184- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-03
OSV
2.6
Improper handling of session establishment errors in xrdp
xrdp is an open source remote desktop protocol (RDP) server. In versions prior to 0.9.23 improper handling of session establishment errors allows bypassing OS-level session restrictions. The auth_start_session function can return non-zero (1) value on, e.g., PAM error which may result in in session restrictions such as max concurrent sessions per user by PAM (ex ./etc/security/limits.conf) to be bypassed. Users (administrators) don't use restrictions by PAM are not affected. This issue has been addressed in release version 0.9.23. Users are advised to upgrade. There are no known workarounds for this issue.
- Record
CVE-2023-40184- CVSS 3.1
- 2.6 Low
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:L - Weakness
- CWE-755
- Updated
- 2026-11-02
OSVDEBIAN-CVE-2023-40184
6.5
xrdp is an open source remote desktop protocol (RDP) server. In versions prior to 0.9.23 improper handling of session establishment errors allows bypassing OS-level session restrictions. The auth_start_session function can return non-zero (1) value on, e.g., PAM error which may result in in session restrictions such as max concurrent sessions per user by PAM (ex ./etc/security/limits.conf) to be bypassed. Users (administrators) don't use restrictions by PAM are not affected. This issue has been addressed in release version 0.9.23. Users are advised to upgrade. There are no known workarounds for this issue.
- Record
DEBIAN-CVE-2023-40184- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
Show 8 moreShow less
OSVUBUNTU-CVE-2023-40184
2.6
xrdp is an open source remote desktop protocol (RDP) server. In versions prior to 0.9.23 improper handling of session establishment errors allows bypassing OS-level session restrictions. The auth_start_session function can return non-zero (1) value on, e.g., PAM error which may result in in session restrictions such as max concurrent sessions per user by PAM (ex ./etc/security/limits.conf) to be bypassed. Users (administrators) don't use restrictions by PAM are not affected. This issue has been addressed in release version 0.9.23. Users are advised to upgrade. There are no known workarounds for this issue.
- Record
UBUNTU-CVE-2023-40184- CVSS 3.1
- 2.6 Low
CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:L - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
OSVMGASA-2023-0276 No score
Updated xrdp packages fix security vulnerability
In versions prior to 0.9.23 improper handling of session establishment
errors allows bypassing OS-level session restrictions. The
auth_start_session function can return non-zero (1) value on, e.g.,
PAM error which may result in session restrictions such as max
concurrent sessions per user by PAM (ex ./etc/security/limits.conf) to
be bypassed. (CVE-2023-40184)
- Record
MGASA-2023-0276- Updated
- 2026-11-02
OSVopenSUSE-SU-2024:13399-1 No score
libpainter0-0.9.23.1-1.1 on GA media
These are all security issues fixed in the libpainter0-0.9.23.1-1.1 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2024:13399-1- Updated
- 2026-11-02
OSVSUSE-SU-2023:3735-1 No score
Security update for xrdp
This update for xrdp fixes the following issues:
- CVE-2023-40184: Fixed restriction bypass via improper session handling (bsc#1214805).
- Record
SUSE-SU-2023:3735-1- Updated
- 2026-11-02
OSVSUSE-SU-2023:3830-1 No score
Security update for xrdp
This update for xrdp fixes the following issues:
- CVE-2023-40184: Fixed restriction bypass via improper session handling (bsc#1214805).
- Record
SUSE-SU-2023:3830-1- Updated
- 2026-11-02
OSVSUSE-SU-2023:4873-1 No score
Security update for xrdp
This update for xrdp fixes the following issues:
- CVE-2023-42822: Fixed unchecked access to font glyph info (bsc#1215803).
- CVE-2023-40184: Fixed restriction bypass via improper session handling (bsc#1214805).
- Record
SUSE-SU-2023:4873-1- Updated
- 2026-11-02
OSVUSN-6474-1 No score
xrdp vulnerabilities
It was discovered that xrdp incorrectly handled validation of client-supplied data, which could lead to out-of-bounds reads. An attacker could possibly use this issue to crash the program or extract sensitive information. (CVE-2022-23479, CVE-2022-23481, CVE-2022-23483, CVE-2023-42822)
It was discovered that xrdp improperly handled session establishment errors. An attacker could potentially use this issue to bypass the OS-level session restrictions by PAM. (CVE-2023-40184)
It was discovered that xrdp incorrectly handled validation of client-supplied data, which could lead to out-of-bounds writes. An attacker could possibly use this issue to cause memory corruption or execute arbitrary code. This issue only affected Ubuntu 18.04 LTS, Ubuntu 20.04 LTS and Ubuntu 22.04 LTS. (CVE-2022-23468)
It was discovered that xrdp incorrectly handled validation of client-supplied data, which could lead to out-of-bounds reads. An attacker could possibly use this issue to crash the program or extract sensitive information. This issue only affected Ubuntu 18.04 LTS, Ubuntu 20.04 LTS and Ubuntu 22.04 LTS. (CVE-2022-23480, CVE-2022-23482, CVE-2022-23484)
It was discovered that xrdp incorrectly handled validation of client-supplied data, which could lead to out-of-bounds reads. An attacker could possibly use this issue to crash the program or extract sensitive information. This issue only affected Ubuntu 20.04 LTS and Ubuntu 22.04 LTS. (CVE-2022-23477, CVE-2022-23493)
It was discovered that xrdp incorrectly handled validation of client-supplied data, which could lead to out-of-bounds writes. An attacker could possibly use this issue to cause memory corruption or execute arbitrary code. This issue only affected Ubuntu 20.04 LTS and Ubuntu 22.04 LTS. (CVE-2022-23478)
It was discovered that xrdp incorrectly handled validation of client-supplied data, which could lead to out-of-bounds reads. An attacker could possibly use this issue to crash the program or extract sensitive information. This issue only affected Ubuntu 22.04 LTS. (CVE-2022-23613)
- Record
USN-6474-1- Updated
- 2026-11-02
OSVUSN-8476-1 No score
xrdp vulnerabilities
It was discovered that xrdp incorrectly handled bounds checking when processing user domain information during the connection sequence. An unauthenticated remote attacker could use this issue to cause xrdp to crash, resulting in a denial of service, or possibly execute arbitrary code. (CVE-2025-68670)
It was discovered that xrdp did not correctly enforce the maximum number of login attempts configured by the MaxLoginRetry parameter. A remote attacker could use this issue to perform an unlimited number of login attempts. (CVE-2024-39917)
It was discovered that xrdp did not perform bounds checking when accessing font glyphs. Since some of this data is controllable by the user, a remote attacker could use this issue to cause xrdp to read out of bounds. This issue only affected Ubuntu 24.04 LTS. (CVE-2023-42822)
It was discovered that xrdp did not properly handle session establishment errors. A remote attacker could use this issue to bypass OS-level session restrictions enforced by PAM, such as the maximum number of concurrent sessions per user. This issue only affected Ubuntu 24.04 LTS. (CVE-2023-40184)
- Record
USN-8476-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
xrdpAlpine:v3.18 |
before 0.9.23-r0 | 0.9.23-r0 |
xrdpAlpine:v3.19 |
before 0.9.23-r0 | 0.9.23-r0 |
xrdpAlpine:v3.20 |
before 0.9.23-r0 | 0.9.23-r0 |
xrdpAlpine:v3.21 |
before 0.9.23-r0 | 0.9.23-r0 |
xrdpAlpine:v3.22 |
before 0.9.23-r0 | 0.9.23-r0 |
xrdpAlpine:v3.23 |
before 0.9.23-r0 | 0.9.23-r0 |
xrdpAlpine:v3.24 |
before 0.9.23-r0 | 0.9.23-r0 |
xrdpDebian:12 |
before 0.9.21.1-1+deb12u1, plus listed versions 0.9.21.1-1 |
0.9.21.1-1+deb12u1 |
xrdpDebian:13 |
before 0.9.24-2 | 0.9.24-2 |
xrdpDebian:14 |
before 0.9.24-2 | 0.9.24-2 |
Show 30 moreShow less
| Package | Affected | Fixed |
|---|---|---|
xrdpDebian:11 From an advisory covering 3 CVEs |
before 0.9.21.1-1~deb11u2, plus listed versions 0.9.12-1.10.9.15-10.9.17-10.9.17-20.9.17-2.10.9.19-10.9.21.1-1~deb11u1 |
0.9.21.1-1~deb11u2 |
xrdpMageia:8 |
before 0.9.23-1.mga8 | 0.9.23-1.mga8 |
xrdpMageia:9 |
before 0.9.23-1.mga9 | 0.9.23-1.mga9 |
xrdpSUSE:Linux Enterprise Server 12 SP5 |
before 0.9.10-3.11.1 | 0.9.10-3.11.1 |
xrdpSUSE:Linux Enterprise Server for SAP Applications 12 SP5 |
before 0.9.10-3.11.1 | 0.9.10-3.11.1 |
xrdpSUSE:Linux Enterprise Module for Basesystem 15 SP4 |
before 0.9.13.1-150200.4.24.1 | 0.9.13.1-150200.4.24.1 |
xrdpSUSE:Linux Enterprise Module for Basesystem 15 SP5 |
before 0.9.13.1-150200.4.24.1 | 0.9.13.1-150200.4.24.1 |
xrdpSUSE:Manager Proxy 4.2 |
before 0.9.13.1-150200.4.24.1 | 0.9.13.1-150200.4.24.1 |
xrdpSUSE:Manager Server 4.2 |
before 0.9.13.1-150200.4.24.1 | 0.9.13.1-150200.4.24.1 |
xrdpopenSUSE:Leap 15.4 |
before 0.9.13.1-150200.4.24.1 | 0.9.13.1-150200.4.24.1 |
xrdpopenSUSE:Leap 15.5 |
before 0.9.13.1-150200.4.24.1 | 0.9.13.1-150200.4.24.1 |
xrdpSUSE:Linux Enterprise Server 12 SP5 From an advisory covering 2 CVEs |
before 0.9.10-3.16.1 | 0.9.10-3.16.1 |
xrdpSUSE:Linux Enterprise Server for SAP Applications 12 SP5 From an advisory covering 2 CVEs |
before 0.9.10-3.16.1 | 0.9.10-3.16.1 |
xrdpUbuntu:Pro:14.04:LTS |
before 0.6.0-1ubuntu0.1+esm3, plus listed versions 0.6.0-10.6.0-1ubuntu0.10.6.0-1ubuntu0.1+esm10.6.0-1ubuntu0.1+esm2 |
0.6.0-1ubuntu0.1+esm3 |
xrdpUbuntu:Pro:16.04:LTS |
before 0.6.1-2ubuntu0.3+esm3, plus listed versions 0.6.1-20.6.1-2ubuntu0.10.6.1-2ubuntu0.30.6.1-2ubuntu0.3+esm10.6.1-2ubuntu0.3+esm2 |
0.6.1-2ubuntu0.3+esm3 |
xrdpUbuntu:Pro:18.04:LTS |
before 0.9.5-2ubuntu0.1~esm2, plus listed versions 0.9.1-90.9.4-10.9.4-20.9.4-30.9.4-4 Show 5 moreShow less0.9.4-50.9.5-10.9.5-1build10.9.5-20.9.5-2ubuntu0.1~esm1 |
0.9.5-2ubuntu0.1~esm2 |
xrdpUbuntu:Pro:20.04:LTS |
before 0.9.12-1ubuntu0.1+esm1, plus listed versions 0.9.9-10.9.12-10.9.12-1ubuntu0.1 |
0.9.12-1ubuntu0.1+esm1 |
xrdpUbuntu:Pro:22.04:LTS |
before 0.9.17-2ubuntu2+esm1, plus listed versions 0.9.15-1ubuntu10.9.17-10.9.17-20.9.17-2ubuntu10.9.17-2ubuntu2 |
0.9.17-2ubuntu2+esm1 |
xrdpUbuntu:Pro:24.04:LTS |
before 0.9.24-4ubuntu0.1~esm1, plus listed versions 0.9.21.1-10.9.24-20.9.24-30.9.24-3build10.9.24-3build20.9.24-4 |
0.9.24-4ubuntu0.1~esm1 |
xrdpUbuntu:Pro:14.04:LTS From an advisory covering 13 CVEs |
before 0.6.0-1ubuntu0.1+esm3, plus listed versions 0.6.0-10.6.0-1ubuntu0.10.6.0-1ubuntu0.1+esm10.6.0-1ubuntu0.1+esm2 |
0.6.0-1ubuntu0.1+esm3 |
xrdpUbuntu:Pro:16.04:LTS From an advisory covering 13 CVEs |
before 0.6.1-2ubuntu0.3+esm3, plus listed versions 0.6.1-20.6.1-2ubuntu0.10.6.1-2ubuntu0.30.6.1-2ubuntu0.3+esm10.6.1-2ubuntu0.3+esm2 |
0.6.1-2ubuntu0.3+esm3 |
xrdpUbuntu:Pro:18.04:LTS From an advisory covering 13 CVEs |
before 0.9.5-2ubuntu0.1~esm2, plus listed versions 0.9.1-90.9.4-10.9.4-20.9.4-30.9.4-4 Show 5 moreShow less0.9.4-50.9.5-10.9.5-1build10.9.5-20.9.5-2ubuntu0.1~esm1 |
0.9.5-2ubuntu0.1~esm2 |
xrdpUbuntu:Pro:20.04:LTS From an advisory covering 13 CVEs |
before 0.9.12-1ubuntu0.1+esm1, plus listed versions 0.9.9-10.9.12-10.9.12-1ubuntu0.1 |
0.9.12-1ubuntu0.1+esm1 |
xrdpUbuntu:Pro:22.04:LTS From an advisory covering 13 CVEs |
before 0.9.17-2ubuntu2+esm1, plus listed versions 0.9.15-1ubuntu10.9.17-10.9.17-20.9.17-2ubuntu10.9.17-2ubuntu2 |
0.9.17-2ubuntu2+esm1 |
xrdpUbuntu:Pro:18.04:LTS From an advisory covering 4 CVEs |
before 0.9.5-2ubuntu0.1~esm3, plus listed versions 0.9.1-90.9.4-10.9.4-20.9.4-30.9.4-4 Show 6 moreShow less0.9.4-50.9.5-10.9.5-1build10.9.5-20.9.5-2ubuntu0.1~esm10.9.5-2ubuntu0.1~esm2 |
0.9.5-2ubuntu0.1~esm3 |
xrdpUbuntu:Pro:20.04:LTS From an advisory covering 4 CVEs |
before 0.9.12-1ubuntu0.1+esm2, plus listed versions 0.9.9-10.9.12-10.9.12-1ubuntu0.10.9.12-1ubuntu0.1+esm1 |
0.9.12-1ubuntu0.1+esm2 |
xrdpUbuntu:Pro:22.04:LTS From an advisory covering 4 CVEs |
before 0.9.17-2ubuntu3+esm2, plus listed versions 0.9.15-1ubuntu10.9.17-10.9.17-20.9.17-2ubuntu10.9.17-2ubuntu20.9.17-2ubuntu2+esm10.9.17-2ubuntu30.9.17-2ubuntu3+esm1 |
0.9.17-2ubuntu3+esm2 |
xrdpUbuntu:Pro:24.04:LTS From an advisory covering 4 CVEs |
before 0.9.24-4ubuntu0.1~esm1, plus listed versions 0.9.21.1-10.9.24-20.9.24-30.9.24-3build10.9.24-3build20.9.24-4 |
0.9.24-4ubuntu0.1~esm1 |
xrdpUbuntu:25.10 From an advisory covering 4 CVEs |
before 0.10.1-3.1+deb13u1build0.25.10.1, plus listed versions 0.10.1-30.10.1-3.1 |
0.10.1-3.1+deb13u1build0.25.10.1 |
xrdpopenSUSE:Tumbleweed From an advisory covering 2 CVEs |
before 0.9.23.1-1.1 | 0.9.23.1-1.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| affected, aliases, references | OSV | |
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2023-40184 is a low vulnerability (CVSS 2.6) in Neutrinolabs Xrdp, published August 30, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.85%, the 58th percentile. Fixed in xrdp 0.9.23-r0.
References
github.com/neutrinolabs/xrdp/security/advisories/GHSA-f489-557v-47jq
github.com/neutrinolabs/xrdp/commit/a111a0fdfe2421ef600e40708b5f0168594cfb23
github.com/neutrinolabs/xrdp/blame/9bbb2ec68f390504c32f2062847aa3d821a0089a/sesman/sesexec/session.c
lists.fedoraproject.org/archives/list/[email protected]/message/U5IXMQODV3OIJ7DRQBUQV7PUKNT7SH36
lists.fedoraproject.org/archives/list/[email protected]/message/SOT237TIHTHPX5YNIWLVNINOEYC7WMG2
lists.fedoraproject.org/archives/list/[email protected]/message/URO3FKTFBPNKFARAQBEJLI4MH6YS35P5
Show 34 moreShow less
lists.debian.org/debian-lts-announce/2025/05/msg00018.html
security.alpinelinux.org/vuln/CVE-2023-40184
github.com/CVEProject/cvelistV5/tree/main/cves/2023/40xxx/CVE-2023-40184.json
nvd.nist.gov/vuln/detail/CVE-2023-40184
security-tracker.debian.org/tracker/CVE-2023-40184
advisories.mageia.org/MGASA-2023-0276.html
bugs.mageia.org/show_bug.cgi?id=32276
cve.org/CVERecord?id=CVE-2023-40184
suse.com/support/update/announcement/2023/suse-su-20233735-1
bugzilla.suse.com/1214805
suse.com/security/cve/CVE-2023-40184
suse.com/support/update/announcement/2023/suse-su-20233830-1
suse.com/support/update/announcement/2023/suse-su-20234873-1
bugzilla.suse.com/1215803
bugzilla.suse.com/1217759
suse.com/security/cve/CVE-2023-42822
ubuntu.com/security/CVE-2023-40184
github.com/neutrinolabs/xrdp/commit/25a1fab5b6c5ef2a8bb109232b765cb8b332ce5e
ubuntu.com/security/notices/USN-6474-1
ubuntu.com/security/notices/USN-8476-1
ubuntu.com/security/CVE-2022-23468
ubuntu.com/security/CVE-2022-23477
ubuntu.com/security/CVE-2022-23478
ubuntu.com/security/CVE-2022-23479
ubuntu.com/security/CVE-2022-23480
ubuntu.com/security/CVE-2022-23481
ubuntu.com/security/CVE-2022-23482
ubuntu.com/security/CVE-2022-23483
ubuntu.com/security/CVE-2022-23484
ubuntu.com/security/CVE-2022-23493
ubuntu.com/security/CVE-2022-23613
ubuntu.com/security/CVE-2023-42822
ubuntu.com/security/CVE-2024-39917
ubuntu.com/security/CVE-2025-68670