Trail of Bits public CodeQL queries

This repository contains CodeQL queries developed by Trail of Bits and made available to the public. They are part of our ongoing development efforts and are used in our security audits, vulnerability research, and internal projects. They will evolve over time as we identify new techniques.

Using custom CodeQL queries

The easiest is to download all packs from the GitHub registry:

codeql pack download trailofbits/cpp-queries trailofbits/go-queries

Then verify that new queries are installed:

codeql resolve qlpacks | grep trailofbits

And use the queries for analysis:

codeql database analyze database.db --format=sarif-latest --output=./tob.sarif -- trailofbits/cpp-queries
# or
codeql database analyze database.db --format=sarif-latest --output=./tob.sarif -- trailofbits/go-queries

Queries

C and C++

Cryptography

Name	Description	Severity	Precision
Crypto variable initialized using static key	Finds crypto variables initialized using static keys	error	high
Crypto variable initialized using static password	Finds crypto variables initialized using static passwords	error	high
Crypto variable initialized using weak randomness	Finds crypto variables initialized using weak randomness	error	high
Invalid key size	Tests if keys passed to EVP_EncryptInit and EVP_EncryptInit_ex have the same size as the key size of the cipher used	warning	medium
Memory leak related to custom allocator	Finds memory leaks from custom allocated memory	warning	medium
Memory use after free related to custom allocator	Finds use-after-frees related to custom allocators like BN_new	warning	medium
Missing OpenSSL engine initialization	Finds created OpenSSL engines that may not be properly initialized	warning	medium
Missing error handling	Checks if returned error codes are properly checked	warning	high
Missing zeroization of potentially sensitive random BIGNUM	Determines if random bignums are properly zeroized	warning	medium
Random buffer too small	Finds buffer overflows in calls to CSPRNGs	warning	high
Use of legacy cryptographic algorithm	Detects potential instantiations of legacy cryptographic algorithms	warning	medium

Security

Name	Description	Severity	Precision
Invalid string size passed to string manipulation function	Finds calls to functions that take as input a string and its size as separate arguments (e.g., strncmp, strncat, ...) and the size argument is wrong	error	low
Missing null terminator	This query finds incorrectly initialized strings that are passed to functions expecting null-byte-terminated strings	error	high
Unsafe implicit integer conversion	Finds implicit integer casts that may overflow or be truncated, with false positive reduction via Value Range Analysis	warning	low

Go

Cryptography

Name	Description	Severity	Precision
Message not hashed before signature verification	Detects calls to (EC)DSA APIs with a message that was not hashed. If the message is longer than the expected hash digest size, it is silently truncated	error	medium

Security

Name	Description	Severity	Precision
Invalid file permission parameter	Finds non-octal (e.g., 755 vs 0o755) and unsupported (e.g., 04666) literals used as a filesystem permission parameter (FileMode)	error	medium
Missing MinVersion in tls.Config	This rule finds cases when you do not set the tls.Config.MinVersion explicitly for servers. By default version 1.0 is used, which is considered insecure. This rule does not mark explicitly set insecure versions	error	medium
Trim functions misuse	Finds calls to string.{Trim,TrimLeft,TrimRight} with the 2nd argument not being a cutset but a continuous substring to be trimmed	error	low

Query suites

CodeQL queries are grouped into "suites". To execute queries from a specific suit add its name after a colon: trailofbits/cpp-queries:codeql-suites/tob-cpp-full.qls.

The recommended suit - tob-cpp-code-scanning.qls - is chosen and executed when you do not explicitly specify any suit. Other suits in this repository are:

• tob-<lang>-crypto.qls - queries targeting cryptographic vulnerabilities
• tob-<lang>-security.qls - queries targeting standard security issues
• tob-<lang>-full.qls - all queries, including experimental ones

Development

Prepare environment

Clone this repository and configure global CodeQL's search path:

git clone git@github.com:trailofbits/codeql-queries.git
mkdir -p "${HOME}/.config/codeql/"
echo "--search-path '$PWD/codeql-queries'" > "${HOME}/.config/codeql/config"

Check that CodeQL CLI detects the new qlpacks:

codeql resolve qlpacks | grep trailofbits

Before committing

Run tests:

cd codeql-queries
codeql test run ./cpp/test
codeql test run ./go/test

Update dependencies:

bash ./scripts/install_all.sh

Generate query tables and copy-paste it to README.md file

python ./scripts/queries_table_generator.py 2>/dev/null

Generate markdown query help files

codeql generate query-help ./cpp/src/ --format=markdown --output ./cpp/src/docs
codeql generate query-help ./go/src/ --format=markdown --output ./go/src/docs