CVE-2023-2534 | Information disclouse and DoS via websocket push events

Improper Authorization vulnerability in OTRS AG OTRS 8 (Websocket API backend) allows any as Agent authenticated attacker to track user behaviour and to gain live insight into overall system usage. User IDs can easily be correlated with real names e. g. via ticket histories by any user. (Fuzzing for garnering other adjacent user/sensitive data). Subscribing to all possible push events could also lead to performance implications on the server side, depending on the size of the installation and the number of active users. (Flooding)This issue affects OTRS: from 8.0.X before 8.0.32.

Published: 2023-05-08 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-2534 is rated Moderate Risk (44.7/100): CVSS High severity, with low exploitation likelihood (EPSS 0.53%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-2534

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.32% 0.53% +0.21%
2 2026-05-24 0.36% 0.32% -0.04%
3 2026-05-09 — 0.36% —

Full EPSS history (11 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-2534

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.6 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:L Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:L)
Might cause slowdowns, glitches, or partial disruption—not a full brick.
 2.8 4.7 [email protected]
8.1 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 5.2 [email protected]

Weakness enumeration for CVE-2023-2534

Affected software / configurations for CVE-2023-2534

Vendor Product Version Raw CPE
otrs otrs >= 8.0.0, < 8.0.32 cpe:2.3:a:otrs:otrs:*:*:*:*:*:*:*:*

References for CVE-2023-2534

cvelogic Threat Intelligence