GHSA-x9vc-6hfv-hg8c
HIGHNpgsql vulnerable to SQL Injection via Protocol Message Size Overflow
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
Npgsql.NETNpgsql.NETNpgsql.NETNpgsql.NETNpgsql.NETNpgsqlReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects NuGet packages — download data is not available via public APIs for these ecosystems.
Description
Summary
The WriteBind() method in src/Npgsql/Internal/NpgsqlConnector.FrontendMessages.cs uses int variables to store the message length and the sum of parameter lengths. Both variables overflow when the sum of parameter lengths becomes too large.
This causes Npgsql to write a message size that is too small when constructing a Postgres protocol message to send it over the network to the database. When parsing the message, the database will only read a small number of bytes and treat any following bytes as new messages while they belong to the old message.
Attackers can abuse this to inject arbitrary Postgres protocol messages into the connection, leading to the execution of arbitrary SQL statements on the application's behalf.
Impact
Attackers can issue arbitrary SQL statements to the database on behalf of the application. The final impact depends on the application that uses Npgsql, the data it stores in Postgres, etc.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| .NETNuGet | Npgsql | ≥ 8.0.0&&< 8.0.3 | 8.0.3 |
| .NETNuGet | Npgsql | all versions | 4.0.14 |
| .NETNuGet | Npgsql | ≥ 4.1.0&&< 4.1.13 | 4.1.13 |
| .NETNuGet | Npgsql | ≥ 5.0.0&&< 5.0.18 | 5.0.18 |
| .NETNuGet | Npgsql | ≥ 6.0.0&&< 6.0.11 | 6.0.11 |
| .NETNuGet | Npgsql | ≥ 7.0.0&&< 7.0.7 | 7.0.7 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for Npgsql. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update Npgsql to 8.0.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-x9vc-6hfv-hg8c is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-x9vc-6hfv-hg8c is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-x9vc-6hfv-hg8c. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-x9vc-6hfv-hg8c in your dependencies?
O3 detects GHSA-x9vc-6hfv-hg8c across NuGet dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.