CWE-149
Improper Neutralization of Quoting Syntax
Common consequences1
- IntegrityUnexpected State
Potential mitigations4
Developers should anticipate that quotes will be injected/removed/manipulated in the input vectors of their product. Use an appropriate combination of denylists and allowlists to ensure only valid, expected and appropriate input is processed by the system.
- Implementation
Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does. When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue." Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
- Implementation
While it is risky to use dynamically-generated query strings, code, or commands that mix control and data together, sometimes it may be unavoidable. Properly quote arguments and escape any special characters within those arguments. The most conservative approach is to escape or filter all characters that do not pass an extremely strict allowlist (such as everything that is not alphanumeric or white space). If some special characters are still needed, such as white space, wrap each argument in quotes after the escaping/filtering step. Be careful of argument injection (CWE-88).
- Implementation
Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174). Such errors could be used to bypass allowlist validation schemes by introducing dangerous inputs after they have been checked.
Relationships1
- ChildOfCWE-138
CVEs referencing this CWE5
| CVE | Description | Severity | EPSS | Flags | Modified |
|---|---|---|---|---|---|
| CVE-2025-1094 | Improper neutralization of quoting syntax in PostgreSQL libpq functions PQescapeLiteral(), PQescapeIdentifier(), PQescapeString(), and PQescapeStringConn() allows a database input provider to achieve SQL injection in certain usage patterns. Specifically, SQL injection requires the application to use the function result to construct input to psql, the PostgreSQL interactive terminal. Similarly, improper neutralization of quoting syntax in PostgreSQL command line utility programs allows a source of command line arguments to achieve SQL injection when client_encoding is BIG5 and server_encoding is one of EUC_TW or MULE_INTERNAL. Versions before PostgreSQL 17.3, 16.7, 15.11, 14.16, and 13.19 are affected. | HIGH8.1 | 89%p100 | Weaponized | 2026-04-15 |
| CVE-2023-36479 | Eclipse Jetty Canonical Repository is the canonical repository for the Jetty project. Users of the CgiServlet with a very specific command structure may have the wrong command executed. If a user sends a request to a org.eclipse.jetty.servlets.CGI Servlet for a binary with a space in its name, the servlet will escape the command by wrapping it in quotation marks. This wrapped command, plus an optional command prefix, will then be executed through a call to Runtime.exec. If the original binary name provided by the user contains a quotation mark followed by a space, the resulting command line will contain multiple tokens instead of one. This issue was patched in version 9.4.52, 10.0.16, 11.0.16 and 12.0.0-beta2. | LOW3.1 | 1.01%p58 | 2025-10-16 | |
| CVE-2018-25135 | Anviz AIM CrossChex Standard 4.3.6.0 contains a CSV injection vulnerability that allows attackers to execute commands by inserting malicious formulas in user import fields. Attackers can craft payloads in fields like 'Name', 'Gender', or 'Position' to trigger Excel macro execution when importing user data. | CRITICAL9.8 | 0.59%p44 | 2026-04-15 | |
| CVE-2026-42511 | The BOOTP file field is written to the lease file without escaping embedded double-quotes, allowing injection of arbitrary dhclient.conf directives. When the lease file is subsequently re-parsed by dhclient, e.g., after a system restart, an attacker-controlled field from the lease is passed to dhclient-script(8), which evaluates it. A rogue DHCP server may be able to execute arbirary code as root on a system running dhclient. | HIGH8.1 | 0.43%p34 | 2026-05-01 | |
| CVE-2025-43878 | When running in Appliance mode, an authenticated attacker assigned the Administrator or Resource Administrator role may be able to bypass Appliance mode restrictions utilizing system diagnostics tcpdump command utility on a F5OS-C/A system. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated. | MEDIUM6.0 | 0.15%p4 | 2026-02-26 |