Weakness (CWE)
CWE-176: Improper Handling of Unicode Encoding
The product does not properly handle when an input contains Unicode encoding.
How to prevent it (3 mitigations)
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Architecture and Design
Avoid making decisions based on names of resources (e.g. files) if those resources can have alternate names.
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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.
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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.
Source: MITRE CWE-176
12 results · Clear filters · Feed
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High 7.1
SD JWT JS: Tampered disclosures silently dropped instead of rejected
SD JWT JS is a JavaScript implementation of the Selective Disclosure JWT (SD-JWT) specification. In version 0.19.0 and earlier, `@sd-jwt/decode`, also used by `@sd-jwt/core`, silently drops a tampered Disclosure whose digest no longer matches the Issuer-signe…
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High 7.5
Cpanel::JSON::XS versions from 4.43 before 4.80 for Perl misorder byte-string keys during canonical encoding in utf16_cmp
Cpanel::JSON::XS versions from 4.43 before 4.80 for Perl misorder byte-string keys during canonical encoding in utf16_cmp. canonical sorts keys by UTF-16 code units. When any key in a hash is UTF-8 flagged, every key is decoded as UTF-8 for the comparison, in…
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High 7.5
MOVEit Transfer Email MFA Bypass
Improper handling of unicode encoding vulnerability in Progress MOVEit Transfer. This issue affects MOVEit Transfer: before 2025.1.6 and from 2026.0.0 before 2026.0.4.
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High 7.5
Expat before 2.8.5 Malformed UTF-16 Acceptance via Unchecked Surrogate
Expat before 2.8.5 fails to validate that a high surrogate in UTF-16 input is followed by a low surrogate, allowing malformed UTF-16 sequences to be accepted. Attackers can supply UTF-16 encoded XML containing lone high surrogates that consume the following c…
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High 7.7
A flaw in Node.js TLS hostname handling can cause Node.js unicode dot separator handling can lead to tls wildcard-depth…
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High 8.1
Caddy: Unsafe Unicode Handling in FastCGI splitPos Allows Execution of Non-PHP Files
Caddy is an extensible server platform that uses TLS by default. From 2.7.0 until 2.11.3, the FastCGI transport's splitPos() in modules/caddyhttp/reverseproxy/fastcgi/fastcgi.go misuses golang.org/x/text/search with search.IgnoreCase when the request path con…
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High 7.3
Deno Permission Bypass via Unicode Normalization Mismatch on macOS (APFS)
Deno is a JavaScript, TypeScript, and WebAssembly runtime. Prior to 2.7.14, Deno's permission system enforces filesystem and execution restrictions by comparing the requested path against the path supplied to --deny-read, --deny-write, --deny-run, or --deny-f…
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High 8.1
FrankenPHP: Unsafe Unicode Handling in CGI Path Splitting Allows Execution of Non-PHP Files
FrankenPHP is a modern application server for PHP. From version 1.11.2 to before version 1.12.3, the splitPos() function in cgi.go misuses golang.org/x/text/search with search.IgnoreCase when the request path contains a non-ASCII byte. Two distinct flaws in t…
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High 7.5
Text::Minify::XS versions from 0.3.0 before 0.7.8 for Perl have heap overflow when processing some malformed UTF-8 characters
Text::Minify::XS versions from 0.3.0 before 0.7.8 for Perl have a heap overflow when processing some malformed UTF-8 characters. The minify functions mishandled some malformed UTF-8 characters, leading to heap corruption. Note that the minify_utf8 function is…
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High 7.2
Improper handling of Unicode encoding in SonicWall SMA1000 series appliances allows a remote authenticated SSLVPN user …
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High 8.8
node-tar has Race Condition in Path Reservations via Unicode Ligature Collisions on macOS APFS
node-tar,a Tar for Node.js, has a race condition vulnerability in versions up to and including 7.5.3. This is due to an incomplete handling of Unicode path collisions in the `path-reservations` system. On case-insensitive or normalization-insensitive filesyst…
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High 7.3
In shouldHideDocument of ExternalStorageProvider.java, there is a possible bypass of a file path filter designed to pre…
KEV Nov 7, 2024