CVE-2024-32655 is a high-severity (CVSS 8.1) SQL Injection vulnerability in Npgsql. A fix is available for Npgsql — see the affected versions and patch details below.
Npgsql Vulnerable to SQL Injection via Protocol Message Size Overflow
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2024-32655.
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.
How urgent is this, really
CVE-2024-32655 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,156 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
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 | 8.0.3dotnet add package Npgsql --version 8.0.3 |
| .NETNuGet | Npgsql | all versions | 4.0.14dotnet add package Npgsql --version 4.0.14 |
| .NETNuGet | Npgsql | ≥ 4.1.0&&< 4.1.13 | 4.1.13dotnet add package Npgsql --version 4.1.13 |
| .NETNuGet | Npgsql | ≥ 5.0.0&&< 5.0.18 | 5.0.18dotnet add package Npgsql --version 5.0.18 |
| .NETNuGet | Npgsql | ≥ 6.0.0&&< 6.0.11 | 6.0.11dotnet add package Npgsql --version 6.0.11 |
| .NETNuGet | Npgsql | ≥ 7.0.0&&< 7.0.7 | 7.0.7dotnet add package Npgsql --version 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, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update Npgsql to 8.0.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-32655 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2024-32655 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2024-32655. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2024-32655 in your dependencies?
O3 Security finds CVE-2024-32655 across NuGet dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.