Inefficient Algorithmic Complexity
CWE-407
An algorithm in a product has an inefficient worst-case computational complexity that may be detrimental to system performance and can be triggered by an attacker, typically using crafted manipulations that ensure that the worst case is being reached.
We track 177 vulnerabilities of this type. 100% are rated high or critical, and the average CVSS score is 7.7.
Latest Inefficient Algorithmic Complexity vulnerabilities
- 8.7 High severity
aiohttp: Uncontrolled Resource Consumption
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.4, aiohttp decompresses each member of a payload containing many concatenated gzip, deflate, or zstd streams by passing the entire remaining input to a new decompress
- 8.7 High severity
aiohttp: Inefficient Algorithmic Complexity
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.4, Request.post() does not limit the number of fields in a URL-encoded form body, and inserting many repeated keys into MultiDict takes quadratic time on the event lo
- 7.5 High severity
kit: Inefficient Algorithmic Complexity
SvelteKit is a framework for rapidly developing robust, performant web applications using Svelte. From version 2.42.0 until 3.1.1, applications using the experimental remote functions flag and a remote form function could perform quadratic synchronous work whi
- 7.5 High severity
fleet: Inefficient Algorithmic Complexity
Fleet before 4.86.2 contains a denial of service vulnerability that allows unauthenticated attackers to exhaust server memory through quadratic XML canonicalization of unsigned SAML responses. Attackers can send a single crafted SAML response with deeply neste
- 7.5 High severity
soupsieve: Inefficient Algorithmic Complexity
Soup Sieve is a CSS selector library designed to be used with Beautiful Soup 4. Prior to 4.0, Soup Sieve repeatedly walks the same ancestors while matching descendant combinators, and each additional descendant combinator raises the polynomial degree of the wo
- 7.5 High severity
PapaParse: Inefficient Algorithmic Complexity
PapaParse before 5.7.1 contains an inefficient algorithmic complexity vulnerability that allows remote unauthenticated attackers to cause denial of service by submitting delimiter-free quoted CSV input to Papa.parse(). Attackers can supply a single-column quot
- 7.5 High severity
hMailServer: Inefficient Algorithmic Complexity
Inefficient algorithmic complexity in the JSON reader of Progressive Robot hMailServer 6.3.6 and 6.3.7 allows a remote attacker to hold the server's mail delivery threads or its REST API's worker threads, making mail delivery, the REST API and the webmail unav
- 8.7 High severity
Eclipse Langium: Inefficient Algorithmic Complexity
Eclipse Langium versions 3.2.0 through 4.4.0 contain an inefficient algorithmic complexity issue (CWE-407) in the opt-in IndentationAwareTokenBuilder and IndentationAwareLexer. When producing DEDENT tokens, the token builder recomputes line numbers by re-scann
- 7.5 High severity
hickory-dns: Inefficient Algorithmic Complexity
Hickory DNS hickory-proto from 0.3.1 before 0.26.1 contains a denial of service vulnerability in BinEncoder that allows remote attackers to exhaust CPU through quadratic-time name compression. Attackers can send malicious DNS messages with many records that ad
- 7.5 High severity
zebra: Inefficient Algorithmic Complexity
Zebra before 7.0.0 contains an inefficient algorithmic complexity vulnerability that allows unauthenticated peers to exhaust verification threads by submitting transactions with many transparent inputs. Attackers can relay invalid transactions with tens of tho
- 7.5 High severity
zebra: Inefficient Algorithmic Complexity
Zebra zebrad 6.4.0 before 7.0.0 performs quadratic work in the mempool coinbase-maturity check because Transaction::coinbase_spend_restriction() rebuilds the transaction's output list once per spent outpoint. Any connected peer can repeatedly send unsigned tra
- 8.7 High severity
symfony: Inefficient Algorithmic Complexity
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
- 7.7 High severity
kyverno: Inefficient Algorithmic Complexity
Kyverno before 1.19.2 contains a denial of service vulnerability that allows namespaced policy authors to exhaust admission controller CPU by submitting pathological wildcard patterns. Attackers can create a Policy with crafted match and exclude names evaluate
- 7.5 High severity
jackson-dataformat-cbor: Inefficient Algorithmic Complexity
One CBOR-parsing issue in jackson-dataformats-binary's CBOR module: an unbounded run of CBOR tags drives quadratic-time TagList growth (CPU/GC-exhaustion DoS, PoC-proven). PoC executed against com.fasterxml.jackson.dataformat:jackson-dataformat-cbor:2.18.2; pr
- 7.5 High severity
rsync: Inefficient Algorithmic Complexity
rsync before 3.5.2 contains a denial of service vulnerability in the delta-transfer sender's hash_search() in match.c that allows malicious receivers to trigger unbounded strong-checksum work at consecutive offsets. Unauthenticated attackers pulling from a pub
- 7.5 High severity
mistune: Inefficient Algorithmic Complexity
Mistune from 3.3.0 before 3.3.4 contains a denial of service vulnerability that allows remote attackers to exhaust CPU through quadratic-time emphasis delimiter processing. Attackers can submit small markdown documents with repeated patterns like "*a_b" to tri
- 8.7 High severity
daptin: Uncontrolled Resource Consumption
Daptin is a GraphQL/JSON-API headless CMS. Prior to 0.12.26, the global `LanguageMiddleware` in `server/language.go` passes the raw `Accept-Language` header from `LanguageMiddlewareFunc` through `GetLanguagePreference` to `golang.org/x/text/language.ParseAccep
- 7.5 High severity
pyasn1: Inefficient Algorithmic Complexity
pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.5, binary REAL decoding builds a large mantissa one octet at a time by shifting a growing integer and slicing the remaining byte string. Attacker-controlled ASN.1 includes a binary-encoded REAL with a
- 7.5 High severity
pyasn1: Inefficient Algorithmic Complexity
pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.5, constructed BIT STRING decoding repeatedly shifts and copies the complete bit value accumulated from earlier fragments. Attacker-controlled BER or CER input contains many constructed BIT STRING frag
- 7.5 High severity
pyasn1: Inefficient Algorithmic Complexity
pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.5, constructed string and indefinite-length ANY decoding repeatedly concatenates each fragment onto a growing bytes value. Attacker-controlled BER or CER data can use many constructed OCTET STRING or c
- 7.5 High severity
pyasn1: Inefficient Algorithmic Complexity
pyasn1 is a generic ASN.1 library for Python. From 0.3.3 until 0.6.5, schemaless container decoding stores every decoded component's TagSet in a growing set even though only one-versus-multiple tag types must be distinguished. Attacker-controlled BER, CER, or
- 7.5 High severity
python-markdown2: Inefficient Algorithmic Complexity
python-markdown2 through 2.5.5 contains a denial of service vulnerability that allows remote users to exhaust CPU by submitting Markdown with unclosed inline link destinations. Attackers can submit repeated '[a](' or '.find(), matchAll(), split(), or matcher().replaceAll() can cause qua
- 7.5 High severity
Telerik Document Processing Libraries: Inefficient Algorithmic Complexity
In Progress® Telerik® Document Processing Libraries prior to version 2026.3.1027, uncontrolled recursion, infinite loop, inefficient algorithmic complexity and resource allocation vulnerabilities in RadPdfProcessing and AI document summarization and question a
- 7.5 High severity
Telerik Document Processing Libraries: Inefficient Algorithmic Complexity
In Progress® Telerik® Document Processing Libraries prior to version 2026.3.1027, uncontrolled recursion, inefficient algorithmic complexity and infinite loop vulnerabilities in RadWordsProcessing allow an unauthenticated attacker to terminate or hang the host
- 7.5 High severity
golang.org/x/net/html: Inefficient Algorithmic Complexity
When coalescing adjacent text nodes in addText and fosterParent, appending to an existing TextNode's Data via string concatenation (n.Data += text) reallocated and copied the accumulated string on every token. Inputs containing many short text runs separated b
- 7.5 High severity
svg-sanitizer: Inefficient Algorithmic Complexity
svg-sanitizer from 0.5.3 before 1.1.0 contains a denial of service vulnerability in Sanitizer::sanitize() that repeatedly rescans the whole input while stripping PHP tags. Unauthenticated attackers can upload SVGs with many overlapping PHP tag openers and clos
- 7.5 High severity
SemanticMediaWiki: Inefficient Algorithmic Complexity
Semantic MediaWiki from 3.0.0 before 7.3.1 contains an algorithmic complexity vulnerability in TermParser::normalize_compact_form() that allows unauthenticated attackers to cause quadratic CPU consumption. Attackers can submit long search terms with many disti
- 7.5 High severity
go-jose: Inefficient Algorithmic Complexity
Go JOSE provides an implementation of the Javascript Object Signing and Encryption set of standards in Go, including support for JSON Web Encryption (JWE), JSON Web Signature (JWS), and JSON Web Token (JWT) standards. Prior to 4.1.6, go-jose parses attacker-co
- 8.7 High severity
bandit: Inefficient Algorithmic Complexity
Inefficient Algorithmic Complexity vulnerability in the header integer parser of mtrudel bandit allows an unauthenticated remote attacker to consume server CPU via a content-length value or a Host or :authority port made of thousands of digits. Bandit.Headers.
- 8.7 High severity
bandit: Inefficient Algorithmic Complexity
Inefficient Algorithmic Complexity vulnerability in the HTTP/2 implementation of mtrudel bandit allows an unauthenticated remote attacker to exhaust server CPU via small SETTINGS or connection-level WINDOW_UPDATE frames. The attacker opens thousands of streams
- 7.1 High severity
pypdf: Uncontrolled Resource Consumption
pypdf is a free and open-source pure-python PDF library. Prior to 6.21.2, an incomplete remediation for repeated malformed cross-reference entries in GHSA-55h5-xmcq-c37v could still trigger a complete PDF stream reload during each recovery attempt even when a
- 8.7 High severity
qt: Inefficient Algorithmic Complexity
An attacker able to supply a crafted XML document to an application using QXmlStreamReader can cause disproportionate CPU consumption during parsing, making the application unresponsive (denial of service). Exploitation requires only that the application parse
- 7.5 High severity
mistune: Inefficient Algorithmic Complexity
Mistune before 3.3.0 contains an algorithmic complexity vulnerability in the inline link parser that allows unauthenticated attackers to exhaust CPU by submitting long runs of unmatched '[' characters. Attackers can send small markdown payloads that trigger O(
- 7.5 High severity
mistune: Inefficient Algorithmic Complexity
Mistune before 3.3.0 contains an inefficient algorithmic complexity vulnerability in parse_link_text that allows remote attackers to cause denial of service through unbalanced square brackets. Attackers can submit markdown containing long runs of unmatched bra
- 7.5 High severity
graphql-core: Uncontrolled Resource Consumption
GraphQL-core is a Python port of the GraphQL.js reference implementation. From 3.0.0 until 3.2.12 and 3.3.0rc1, the OverlappingFieldsCanBeMerged rule in specified_rules repeatedly compares fields that share response names and recursively re-compares flattened
- 7.5 High severity
Pillow: Uncontrolled Resource Consumption
Pillow is a Python imaging library. From 5.1.0 until 13.0.0, PdfParser.linearize_page_tree() in src/PIL/PdfParser.py treats a PDF /Pages graph as a tree without tracking duplicate indirect references. When Image.save(..., format="PDF", append=True) processes a
- 8.7 High severity
toml-node: Inefficient Algorithmic Complexity
toml-node is a TOML parser for Node.js and the browser. Prior to 5.0.1, toml.parse() repeatedly slices and rejoins every path prefix in lib/compiler.js while processing long dotted keys, table headers, array-of-tables headers, and inline-table keys in assign()
- 8.7 High severity
toml-node: Inefficient Algorithmic Complexity
toml-node is a TOML parser for Node.js and the browser. Prior to 5.0.1, the toml.parse() compiler's addTableArray() function in lib/compiler.js rescans the complete assignedPaths and valueAssignments bookkeeping sets for every array-of-tables header. Distinct