SQL Injection: What It Is and How to Fix It
SQL injection is a vulnerability where text entered by a visitor is included in a database query not as a value but as part of a command. As a result, an outsider can read, modify, or delete what they should not have access to.
Analogy for Website Owners
There is an archive and a form: "bring case number ___". If someone writes "...and also take the entire cabinet and leave the door open" in the number field, and the employee reads the form entirely as an instruction — they will do it. It is not the archive that is vulnerable, but the habit of stitching instructions from foreign text. The solution is a form where the case number always remains a number and is never read as a command.
What Can Be Lost
| What Happens | What It Leads To |
|---|---|
| Reading foreign tables | Leakage of customer and order databases — along with notifications to people and questions from regulators |
| Access to accounts | Hashes of administrator passwords, access to the admin panel, control over the site |
| Recording foreign code in the database | Infection that returns even after cleaning files — see malicious code on the site |
How This Affects SEO
There is no direct ranking factor here — it is the consequence that hits. Through injection, spam content and hidden links to foreign topics are uploaded to the database. The typical scenario follows: search engines overestimate the site's theme, rankings drop, some pages fall out of the index, and when the domain gets into databases of unsafe sites, browsers show a warning and traffic drops.
How It Looks in the Security Shield Report
The scanner sends one harmless test query to the found parameters and checks if the site returns a database error message. If it does — a finding appears: "SQL Injection Indicator (DB Error)": high severity, class CWE-89, category OWASP A03:2021. The evidence shows a fragment of the error, and the note "requires verification" means that the service records a symptom, not that it hacks the database.
The test is performed only in paid modes and on a verified domain. The scanner looks from the outside and sees only those parameters it found on the pages — the absence of a finding does not mean that there are no injections anywhere. What exactly is checked is in the article about Security Shield.
A database error in the response means that foreign text has reached the query. Pass the page address and parameter name from the report to the developer. Manual escaping of quotes and "blacklists" of words are not a solution here.
How to Fix It
- Parameterized Queries. The main solution: the query text is set in advance, and values are passed separately — as a prepared statement. Then the content of the field physically cannot become part of the command.
- ORM or Framework Query Layer. Modern libraries do this by default; problems arise where the query is assembled manually as a string.
- Minimal Database User Rights. The site's account almost never needs rights to delete tables and work with files.
- Hide Technical Errors from Visitors — debug output should go to logs, not to the page.
- Update CMS and Extensions. On typical sites, injection often comes from a vulnerable plugin rather than your code.
How to Prevent It from Happening Again
Agree with the developer that queries assembled by concatenating strings do not pass review. A firewall in front of the site is a temporary measure while fixing, not a replacement for prepared statements. After fixing, repeat a deep scan. It is also useful to check with the site audit — it will show foreign pages and links if something has already entered the database.