VulnerabilityPublished 19 Mar 2026Updated 8 Apr 2026

CVE-2026-3658: Appointment Booking Calendar (WordPress plugin) · SQL Injection

Affects Appointment Booking Calendar (WordPress plugin)Source CVE Database V5

Compare

Not known to be exploited · CVSS 7.5 High.

Data as of 30 Oct 2026, 20:25 UTC

CVSS 3.1 base score

7.5High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.3% chance of exploitation in 30 days – higher than 24% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: None
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 19 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
croixhaugAppointment Booking Calendar — Simply Schedule Appointments Booking Plugin	Affected <=1.6.10.0	Fixed in–

AI-suggested

Until an official fix is released, users should consider disabling or removing the vulnerable plugin to prevent exploitation. Monitoring for updates from the vendor or trusted security sources is recommended.

Description

The Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin plugin for WordPress is vulnerable to SQL Injection via the 'fields' parameter in all versions up to, and including, 1.6.10.0 due to insufficient escaping on the user supplied parameter and lack of sufficient preparation on the existing SQL query. This makes it possible for unauthenticated attackers to append additional SQL queries into already existing queries that can be used to extract sensitive information from the database, including usernames, email addresses, and password hashes.

Impact

Successful exploitation of this vulnerability can lead to unauthorized disclosure of sensitive information stored in the plugin's database, including usernames, email addresses, and password hashes. This compromises confidentiality but does not affect integrity or availability according to the CVSS vector. The vulnerability is remotely exploitable without authentication, increasing its risk profile.

CWE-89Improper Neutralization of Special Elements used in an SQL Command (SQL Injection) (opens in a new tab)
Base weaknessLikelihood of exploit: HighCWE Top 25 (2025): #2OWASP Top 10 A05:2025: Injection (opens in a new tab)
The product constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component. Without sufficient removal or quoting of SQL syntax in user-controllable inputs, the generated SQL query can cause those inputs to be interpreted as SQL instead of ordinary user data.
Architecture and Design · Libraries or Frameworks
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Architecture and Design · Parameterization
If available, use structured mechanisms that automatically enforce the separation between data and code. These mechanisms may be able to provide the relevant quoting, encoding, and validation automatically, instead of relying on the developer to provide this capability at every point where output is generated.
Architecture and Design · Operation · Environment Hardening
Run your code using the lowest privileges that are required to accomplish the necessary tasks. If possible, create isolated accounts with limited privileges that are only used for a single task. That way, a successful attack will not immediately give the attacker access to the rest of the software or its environment.
OWASP Cheat Sheets
Query Parameterization (opens in a new tab)
Unvalidated Redirects and Forwards (opens in a new tab)
XML Security (opens in a new tab)
XML External Entity Prevention (opens in a new tab)
File Upload (opens in a new tab)
OWASP ASVS 4.0.3
V5.3.4 (opens in a new tab)
V5.3.5 (opens in a new tab)
V1.5.1 (opens in a new tab)
Attack patterns
Command Line Execution through SQL Injection (opens in a new tab)
Object Relational Mapping Injection (opens in a new tab)
SQL Injection through SOAP Parameter Tampering (opens in a new tab)
Expanding Control over the Operating System from the Database (opens in a new tab)
SQL Injection (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 9 Apr 2026, 18:49 UTC

WeaknessesCWE-89

Technical details

References

Community reviews

Related threats