Weakness (CWE)
CWE-1286: Improper Validation of Syntactic Correctness of Input
The product receives input that is expected to be well-formed - i.e., to comply with a certain syntax - but it does not validate or incorrectly validates that the input complies with the syntax.
How to prevent it (1 mitigation)
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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.
Source: MITRE CWE-1286
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High 8.8CVE-2026-88009 Public exploit
Traefik: Rootless HTTP/1 request-target routes as "/" but is forwarded verbatim, bypassing path-scoped routing, middleware guards and access logging
Traefik is an open source HTTP reverse proxy and load balancer. Prior to 2.11.57, and 3.7.13, Traefik accepts a rootless HTTP/1 request target that Go stores in URL.Opaque while leaving URL.Path empty. The rewriteRequestBuilder path evaluates routing, path sa…
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High 8.6CVE-2026-50131 Public exploit
Fedify has an incomplete SSRF mitigation after GHSA-p9cg-vqcc-grcx: validatePublicUrl allows special-use IPv4 ranges
Fedify is a TypeScript library for building federated server apps powered by ActivityPub. Fedify previously addressed SSRF/internal network access in GHSA-p9cg-vqcc-grcx by adding public URL validation before runtime document and media fetching. However, the …
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Medium 4.8CVE-2026-34835 Public exploit
Rack: `Rack::Request` accepts invalid Host characters, enabling host allowlist bypass.
Rack is a modular Ruby web server interface. From versions 3.0.0.beta1 to before 3.1.21, and 3.2.0 to before 3.2.6, Rack::Request parses the Host header using an AUTHORITY regular expression that accepts characters not permitted in RFC-compliant hostnames, in…
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High 8.3CVE-2026-25513 Public exploit
FacturaScripts has SQL Injection vulnerability in API ORDER BY Clause
FacturaScripts is open-source enterprise resource planning and accounting software. Prior to version 2025.81, FacturaScripts contains a critical SQL injection vulnerability in the REST API that allows authenticated API users to execute arbitrary SQL queries t…
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Critical 9.8
SPIP porte_plume Plugin Arbitrary PHP Execution
The porte_plume plugin used by SPIP before 4.30-alpha2, 4.2.13, and 4.1.16 is vulnerable to an arbitrary code execution vulnerability. A remote and unauthenticated attacker can execute arbitrary PHP as the SPIP user by sending a crafted HTTP request.