CVE-2026-117554: Admidio before 5.0.17 Event Guest Restriction Bypass via events_function.php
Noroxi assessment
Priority: Monitor (action score 21/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.28% (FIRST EPSS).
- Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: admidio admidio 5.0.17.
Low priority for now. Upgrade to admidio admidio 5.0.17 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
Admidio before 5.0.17 contains an improper access control vulnerability that allows authenticated members to register event guests by submitting the additional_guests field when guests are disallowed. Attackers can set additional_guests to the remaining seat count in modules/events/events_function.php to exhaust event capacity and block other members from registering.
- Published
- Oct 27, 2026
- Updated
- Nov 2, 2026
- EPSS
- 0.2% · 21th percentile
- CWE
- CWE-602
Report tools
Action score
21
Low priority for now.
- CVSS
- 21 / 40 · 5.3 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.2%
CISA SSVC decision
- Exploitation
- proof of concept
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · VulnCheck
- 5.3
- NVD has not scored this yet; the score shown is the CNA’s.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
Is your version affected? Check itNoroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
—
Versions reported by the vendor
Affected version ranges reported by the assigning authority (VulnCheck). Independent of NVD's CPE analysis and usually ahead of it.
admidio admidio
- before 5.0.17affected · semver
Same product
admidio: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-32817Admidio is Missing Authorization and CSRF Protection on Document and Folder Deletion36Monitor
- CVE-2026-32756Admidio: Unrestricted File Upload via CSRF Token Validation Bypass in Documents & Files Module35Monitor
- CVE-2024-38529Admidio Vulnerable to RCE via Arbitrary File Upload in Message Attachment35Monitor
Published before and after this one in the same product
- ← EarlierCVE-2026-111913Oct 17, 2026 · Admidio 5.0.0 before 5.0.16 Authorization Bypass via pdfl Mode in lists_show.php21Monitor
- ← EarlierCVE-2026-111914Oct 17, 2026 · Admidio 5.0.11 before 5.0.16 Broken Access Control via inventory_data.php28Monitor
- ← EarlierCVE-2026-111916Oct 17, 2026 · Admidio before 5.0.16 Information Disclosure via rss/links.php Weblinks Feed27Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| admidio admidio | 5.0.17 | Vendor (CNA) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
- Published
- Fix recordedsame day
- TodayNov 13, 2026+17 d
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
- gwangwon0807finder
- choewonwoo1817finder
- J0hnathanKimfinder
- Kamba-netizenfinder
- t-211finder
- xo0102finder
- Fasseremediation developer
Not on record for this CVE: variant or chain candidate · public bounty program.
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- Integrity
- Availability
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- X
Weakness class (CWE)
CWE-602 · Client-Side Enforcement of Server-Side SecurityCVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
nvd-secondary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
- Manipulating Hidden FieldsCAPEC-162High
- Create Malicious ClientCAPEC-202Medium
- Removing Important Client FunctionalityCAPEC-207likelihood: Medium · High
- Removing/short-circuiting 'Purse' logic: removing/mutating 'cash' decrementsCAPEC-208Medium
- Exploitation of Trusted IdentifiersCAPEC-21likelihood: High · High
- Accessing/Intercepting/Modifying HTTP CookiesCAPEC-31likelihood: High · High
- Harvesting Information via API Event MonitoringCAPEC-383Low
- Application API Message Manipulation via Man-in-the-MiddleCAPEC-384Low
Change log
- SSVC exploitation— → poc
- Exploit maturity— → none
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (6 more)Show less
- github.com/Admidio/admidio/blob/v5.0.16/modules/events/events_function.php#L446-L462
- github.com/Admidio/admidio/commit/5b0ee3585d2a69a6e85fee00b7b93f3ebc1e44d9
- github.com/Admidio/admidio/issues/2231
- github.com/Admidio/admidio/releases/tag/v5.0.17
- github.com/Admidio/admidio/security/advisories/GHSA-92g9-59rr-c3qg
- www.vulncheck.com/advisories/admidio-before-5.0.17-event-guest-restriction-bypass-via-events-function-php
Vendor advisories and official records. Exploit/PoC links are deliberately left out.