| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| The Symfony Yaml components Inline and Parser, parse some YAML documents inefficiently, so that a small crafted document can take disproportionately long to process, keeping a PHP process busy for seconds or minutes, potentially causing a denial of service in Symfony versions prior to 5.4.56, 6.x prior to 6.4.50, 7.x prior to 7.4.23, and 8.x prior to 8.1.11.
The parser repeats work it has already done in several places. An embedded mapping in a flow sequence is parsed again for every scalar appended to it, and so are the collections nested in it, so the parse time grows exponentially with the nesting depth. The patterns matching mapping keys and tags scan a run of spaces once per character of the run, and each scalar of a flow collection is matched against a copy of the rest of the collection, so the parse time grows quadratically with the size of the input. Nested blocks are also copied at each nesting level, which consumes memory as well as time. A few other constructs, such as an empty sequence item followed by a blank line or an anchor named 0, trigger similar repeated work.
Any code parsing untrusted YAML is affected, with the default flags. In Symfony 7.4 and later, that includes #[MapRequestPayload] when the Yaml component is installed and the endpoint does not restrict acceptFormat. A single unauthenticated request with a YAML content type keeps a PHP worker busy until max_execution_time. JSON documents are valid YAML, so a JSON payload sent with a YAML content type is enough for the flow collection case. In Symfony 6.4, #[MapRequestPayload] accepts YAML only when the application registers a yaml request format. |
| HTTP::Body versions before 1.24_01 for Perl allow CPU exhaustion via regex backtracking on the filename of a multipart upload.
For every file part, the multipart parser finds the suffix of the uploaded filename by matching the default $basename_regexp, qr/[^.]+(\.[^\\\/]+)$/, against the whole basename. A basename made of many dots and ending in a backslash makes the regex backtrack in time quadratic in its length.
A remote attacker can exhaust CPU with one request, as a basename of about 32 KB takes several seconds to match and every file part is matched separately. |
| MIME::Field::ParamVal versions before 5.521 for Perl allow CPU exhaustion via unclosed comments in header parameters.
The comment pattern used to parse Content-Type and Content-Disposition parameters scans from each "(" to the next ")". In a field with no ")", every "(" scans to the end of the header and fails, so parsing takes time quadratic in the header length. The field is parsed again on each attribute lookup, several times per MIME entity.
A 40 KB header takes about 7 seconds to parse once. |
| HTTP::Body versions before 1.23_01 for Perl allow CPU exhaustion via quadratic regex backtracking when parsing chunked request bodies.
In chunked mode, used when no content length is given, add() matches each chunk-size line with `/^([\da-fA-F]+).*\x0D\x0A/`. On a line of hex digits whose first LF has no CR before it, the digits and `.*` backtrack against each other, so a single add() takes time quadratic in the line's length. Nothing limits how long the line can be.
A remote attacker can exhaust CPU in applications that pass chunked request bodies to HTTP::Body. |
| A vulnerability was detected in Delgan loguru 0.7.3. The affected element is the function AnsiParser.feed of the file loguru/_colorizer.py of the component ANSI Color-Markup Parser. Performing a manipulation results in inefficient regular expression complexity. The attack is possible to be carried out remotely. The exploit is now public and may be used. The vendor was contacted early about this disclosure but did not respond in any way. |
| A flaw was found in dash. When built without libc fnmatch, the internal pmatch() matcher implements * by unbounded recursion over candidate positions. A local user who can plant filenames, or otherwise feed that matcher, can make a short multi-star pattern such as *.*.*.*.*.tar.gz consume excessive CPU. |
| Wekan is open source kanban built with Meteor. Prior to 11.11, the user-search publication in server/publications/users.js and the searchUsers method in server/models/users.js pass authenticated user-controlled searchTerm and query values to new RegExp() without escaping regular-expression metacharacters. MongoDB-backed deployments evaluate the resulting patterns with PCRE2, allowing a logged-in user to submit catastrophic-backtracking expressions that consume database CPU and degrade or deny service to other users; searchUsers additionally requires board membership or site-admin status. The FerretDB v1 / RE2 unaffected configuration is not practically affected by catastrophic backtracking. This issue is fixed in version 11.11. |
| n8n before 1.123.85, 2.43.5, and 2.44.1 contains a regular expression denial of service vulnerability that allows authenticated members to block the event loop via crafted glob patterns. Attackers who can create and run workflows can submit a wildcard-heavy File(s) Selector pattern causing exponential backtracking, making the UI, API, webhooks, and health checks unresponsive until restart. |
| js-toml is a TOML parser for JavaScript, fully compliant with the TOML 1.0.0 Spec. Versions up to and including 1.1.1 parse hexadecimal / octal / binary integer literals via a hand-written `parseBigInt` loop that multiplies a `BigInt` accumulator by the radix once per input digit. Each iteration performs a `BigInt * BigInt` operation on an accumulator that grows linearly with the number of digits already consumed, so the whole loop is O(n²) in the literal length. The lexer regex places no upper bound on the literal length, so a single TOML document containing one ~500 kB hex literal pins one CPU core for ~40 seconds on a modern laptop (Apple M-series, Node v22). Memory amplification is bounded but CPU amplification is severe and grows quadratically: doubling the literal length quadruples the work. A caller that invokes `load()` on attacker-controlled TOML (configuration upload endpoints, CI/CD systems ingesting third-party `*.toml`, IDE plugins, build tools) is exposed to a single-request CPU exhaustion DoS. Version 1.1.2 fixes the issue. |
| joi is a schema description language and data validator for JavaScript. From 17.1.1 until 17.13.9 and 18.3.1, the Joi.string().email({ multiple: true }) rule uses a separator regular expression whose leading whitespace quantifier is retried at every position in a long whitespace run that contains no separator, causing quadratic work during String.prototype.split. The behavior applies to the default separator and every custom separator. Applications that validate attacker-controlled values with the multiple option and no effective prior length limit can have the Node.js event loop blocked for seconds by one request, preventing other work. A .max() rule is not sufficient when abortEarly: false allows the email rule to run after the maximum-length check fails. This vulnerability is fixed in versions 17.13.9 and 18.3.1. |
| @hapi/content provides HTTP Content-* header parsing. From 3.0.6 until 6.0.3, Content.disposition() uses an unanchored parameter-name expression in a global regular-expression scan, causing repeated failed matching over the remaining input when a Content-Disposition parameter contains a long token without an equals sign. The resulting quadratic processing can block the Node.js event loop before route handlers or validation when @hapi/pez parses multipart/form-data headers, including unauthenticated hapi routes with payload.multipart enabled, and also affects applications that pass untrusted headers directly to Content.disposition(). This issue is fixed in @hapi/content version 6.0.3. |
| HTTP::Headers::ActionPack versions before 0.10 for Perl allow CPU exhaustion via Accept-Language ranges matched as regular expressions.
_language_match interpolates each Accept-Language range into the pattern `/^$range\-/i` without escaping it, so regular expression syntax in the header reaches the regex engine. A 12-byte range such as `(a?|b?){26}z` backtracks for seconds, and each increment of the quantifier doubles the time. An invalid range such as `(` fails to compile.
A remote attacker can exhaust CPU, or make choose_language die, in any application that passes an untrusted Accept-Language header to it. |
| GraphQL Scalars is a library of custom GraphQL scalars for creating precise type-safe GraphQL schemas. From 1.24.1 until 2.0.1, GraphQLPhoneNumber in src/scalars/PhoneNumber.ts uses ambiguous nested digit quantifiers that backtrack exponentially when a PhoneNumber value contains a run of digits followed by a character that makes the match fail. GraphQL evaluates parseLiteral during document validation and parseValue during variable coercion before resolver authentication or authorization, so a small unauthenticated request can block the Node.js event loop and stall the server process. serialize is also affected when unvalidated stored values are returned through the scalar. This issue is fixed in version 2.0.1. |
| EspoCRM before 9.3.11 and 10.x before 10.0.8 contains a denial of service vulnerability in which the password-redaction regular expression applied during API error handling consumes excessive CPU on long request bodies. Unauthenticated remote attackers can concurrently send a small number of large API requests to exhaust server workers, making EspoCRM slow or unavailable to legitimate users. |
| opentelemetry-java is the Java implementation of the OpenTelemetry API for recording telemetry, and SDK for managing telemetry recorded by the API. Prior to 1.67.0, W3CTraceContextPropagator.extract() uses regex delimiter processing that can exhibit quadratic backtracking while parsing tracestate headers containing long runs of spaces or tabs without a following comma. An unauthenticated attacker whose headers reach extraction can repeatedly block request or event-loop threads and cause excessive CPU consumption, with practical impact bounded by ingress header-size limits, proxy configuration, and threading. This issue is fixed in version 1.67.0. |
| RE2JS is the JavaScript port of RE2, a regular expression engine that provides linear time matching. From 2.2.0 until 2.8.7, enabling LOOKBEHINDS and using repeated matching through matcher().find(), matchAll(), split(), or matcher().replaceAll() can cause quadratic total work. Machine.match restarts lookbehind scanning from offset zero for each requested start position, while Matcher-based APIs request capture slots that prevent the early exit used for captureless matching. Dense matches therefore repeatedly rescan the input, allowing attacker-influenced text to monopolize a single-threaded worker and deny service. This issue is fixed in version 2.8.7. |
| Ring is a Clojure web applications library inspired by Python's WSGI and Ruby's Rack. Prior to 1.15.5, `wrap-nested-params` in the `ring.middleware.nested-params` namespace uses a backtracking regular expression to match parameter names from URL query strings and HTTP request bodies. An attacker can craft a parameter name that drives quadratic O(n^2) matching work, causing regular-expression denial of service in applications using the middleware. `Ring-Defaults` users are also exposed because nested-params is enabled by default. Applications omitting the middleware do not expose this parsing path. This issue is fixed in version 1.15.5. |
| Datadog dd-trace-py is the Datadog Python APM client. From 1.5.0 until 3.19.9 and 4.15.6, the default query-string obfuscation regular expression can exhibit excessive backtracking while synchronously processing attacker-controlled URL query strings for HTTP span metadata. A remote attacker can cause prolonged CPU consumption, request latency, and service unavailability in affected HTTP tracing integrations that include query strings in URL span tags. The vulnerable processing is enabled by default for those integrations. This issue is fixed in versions 3.19.9 and 4.15.6. |
| pypdf is a free and open-source pure-python PDF library. Prior to version 6.6.0, pypdf has possible long runtimes for malformed startxref. An attacker who uses this vulnerability can craft a PDF which leads to possibly long runtimes for invalid startxref entries. When rebuilding the cross-reference table, PDF files with lots of whitespace characters become problematic. Only the non-strict reading mode is affected. Only the non-strict reading mode is affected. This issue has been patched in version 6.6.0. |
| Starman versions before 0.4019 for Perl allow CPU exhaustion via quadratic regex backtracking when parsing chunked request bodies.
Starman decodes chunked request bodies before calling the application, matching each chunk-size line with `s/^(([0-9a-fA-F]+).*\015\012)//`. A line of hex digits followed by a bare LF and then CRLF never matches, because `.` does not match LF, and each failed attempt backtracks in time quadratic in the length of the hex run. Nothing limits the length of the line.
A remote attacker can exhaust worker CPU by sending such requests to any route. |
