CVE-2026-40077 | Beszel has an IDOR in hub API endpoints that read system ID from URL parameter

Exp

Beszel is a server monitoring platform. Prior to 0.18.7, some API endpoints in the Beszel hub accept a user-supplied system ID and proceed without further checks that the user should have access to that system. As a result, any authenticated user can access these routes for any system if they know the system's ID. System IDs are random 15 character alphanumeric strings, and are not exposed to all users. However, it is theoretically possible for an authenticated user to enumerate a valid system ID via web API. To use the containers endpoints, the user would also need to enumerate a container ID, which is 12 digit hexadecimal string. This vulnerability is fixed in 0.18.7.

Published: 2026-04-09 Last update: 2026-04-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-40077 is rated Exploit Available (50/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.05%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

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

Public exploit references (Exploit-DB) for CVE-2026-40077

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2026-40077

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 2026-04-15 0.05% 0.05% +0.01%
2 2026-04-10 0.05%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-40077

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
3.5 3.1 LOW
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:N 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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
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:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
1.8 1.4 [email protected]
3.1 3.1 LOW
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N 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:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
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:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
1.6 1.4 [email protected]

Weakness enumeration for CVE-2026-40077

GitHub Security Advisory for CVE-2026-40077

GHSA-5f5r-95pg-xrpm · Severity: low · Ecosystem: go — Beszel has an IDOR in hub API endpoints that read system ID from URL parameter

OS Trackers for CVE-2026-40077

vendor priority summary link
alpine CVE-2026-40077: 1 source package rows (beszel); 13 state rows across 2 repos (3.23-community, edge-community); fixed 0, open 13. https://security.alpinelinux.org/vuln/CVE-2026-40077

Affected software / configurations for CVE-2026-40077

Vendor Product Version Raw CPE
beszel beszel < 0.18.7 cpe:2.3:a:beszel:beszel:*:*:*:*:*:*:*:*

References for CVE-2026-40077

cvelogic Threat Intelligence