CWE-625
Permissive Regular Expression
Extended description
This effectively causes the regexp to accept substrings that match the pattern, which produces a partial comparison to the target. In some cases, this can lead to other weaknesses. Common errors include: not identifying the beginning and end of the target string using wildcards instead of acceptable character ranges others
Common consequences1
- Access ControlBypass Protection Mechanism
Potential mitigations1
- Implementation
When applicable, ensure that the regular expression marks beginning and ending string patterns, such as "/^string$/" for Perl.
CVEs referencing this CWE9
| CVE | Description | Severity | EPSS | Flags | Modified |
|---|---|---|---|---|---|
| CVE-2018-8926 | Permissive regular expression vulnerability in synophoto_dsm_user in Synology Photo Station before 6.8.5-3471 and before 6.3-2975 allows remote authenticated users to conduct privilege escalation attacks via the fullname parameter. | NONE | 1.71%p74 | 2024-11-21 | |
| CVE-2023-6544 | A flaw was found in the Keycloak package. This issue occurs due to a permissive regular expression hardcoded for filtering which allows hosts to register a dynamic client. A malicious user with enough information about the environment could jeopardize an environment with this specific Dynamic Client Registration and TrustedDomain configuration previously unauthorized. | MEDIUM5.4 | 1.08%p61 | 2026-04-15 | |
| CVE-2026-23651 | Permissive regular expression in Azure Compute Gallery allows an authorized attacker to elevate privileges locally. | MEDIUM6.7 | 0.59%p44 | 2026-04-14 | |
| CVE-2020-8910 | A URL parsing issue in goog.uri of the Google Closure Library versions up to and including v20200224 allows an attacker to send malicious URLs to be parsed by the library and return the wrong authority. Mitigation: update your library to version v20200315. | MEDIUM6.5 | 0.52%p40 | 2024-11-21 | |
| CVE-2026-32973 | OpenClaw before 2026.3.11 contains an exec allowlist bypass vulnerability where matchesExecAllowlistPattern improperly normalizes patterns with lowercasing and glob matching that overmatches on POSIX paths. Attackers can exploit the ? wildcard matching across path segments to execute commands or paths not intended by operators. | CRITICAL9.8 | 0.41%p32 | 2026-03-30 | |
| CVE-2026-44587 | CarrierWave is a framework to upload files from Ruby applications. In versions prior to 2.2.7 and 3.1.3, the content_type_denylist check fails to escape regex metacharacters in string entries, causing the denylist to silently not match the content types it is intended to block. In lib/carrierwave/uploader/content_type_denylist.rb:57, denylist entries are interpolated directly into a regex without Regexp.quote or anchoring, so an entry such as image/svg+xml becomes the pattern /image\/svg+xml/, in which + is treated as a quantifier rather than a literal character and therefore never matches the real MIME type image/svg+xml. This is inconsistent with the allowlist implementation, which correctly applies both Regexp.quote and a \A anchor. Other content types containing regex metacharacters, such as application/xhtml+xml, are affected as well. As a result, any application that relies on content_type_denylist to block image/svg+xml, most commonly to prevent stored XSS, is silently unprotected. An attacker can upload an SVG file containing arbitrary JavaScript; if the application serves that SVG inline from its own origin, the script executes in the victim's browser, resulting in stored XSS. This issue has been fixed in versions 2.2.7 and 3.1.3. | MEDIUM4.7 | 0.37%p28 | 2026-06-17 | |
| CVE-2026-34763 | Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Directory interpolates the configured root path directly into a regular expression when deriving the displayed directory path. If root contains regex metacharacters such as +, *, or ., the prefix stripping can fail and the generated directory listing may expose the full filesystem path in the HTML output. This issue has been patched in versions 2.2.23, 3.1.21, and 3.2.6. | MEDIUM5.3 | 0.24%p15 | 2026-05-13 | |
| CVE-2026-34830 | Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Sendfile#map_accel_path interpolates the value of the X-Accel-Mapping request header directly into a regular expression when rewriting file paths for X-Accel-Redirect. Because the header value is not escaped, an attacker who can supply X-Accel-Mapping to the backend can inject regex metacharacters and control the generated X-Accel-Redirect response header. In deployments using Rack::Sendfile with x-accel-redirect, this can allow an attacker to cause nginx to serve unintended files from configured internal locations. This issue has been patched in versions 2.2.23, 3.1.21, and 3.2.6. | HIGH7.5 | 0.21%p11 | 2026-05-13 | |
| CVE-2026-37737 | sanic-cors version 2.2.0 and prior contains an improper regular expression in the try_match() function in sanic_cors/core.py that uses re.match without end-anchoring. This allows an attacker to bypass CORS origin allowlists by registering a domain that begins with a trusted origin string, to gain unauthorized access to cross-origin requests for authenticated resources. | MEDIUM6.5 | 0.16%p6 | 2026-06-05 |