CyberSecBulletin

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

  • 7.5 High severity

    commonmark: Inefficient Algorithmic Complexity

    CVE-2026-86434Thephpleague

    league/commonmark versions >= 2.0.0 and < 2.8.4 (patched in 2.9.0) contain a denial of service vulnerability in UniqueSlugNormalizer::normalize(), which restarts its numeric-suffix search from 1 on every slug collision, resulting in O(K^2) time complexity for

  • 7.5 High severity

    commonmark: Inefficient Algorithmic Complexity

    CVE-2026-86433Thephpleague

    commonmark versions from 1.5.0 before 2.8.4 contain a denial of service vulnerability in the Attributes extension where AttributesListener::findTargetAndDirection() performs quadratic-time sibling list scanning. Unauthenticated attackers can submit approximate

  • 7.5 High severity

    commonmark: Inefficient Algorithmic Complexity

    CVE-2026-86430Thephpleague

    league/commonmark versions before 2.9.1 contain multiple denial of service vulnerabilities in fenced code block detection, reference link label lookup, and emphasis delimiter processing that perform super-linear work on crafted input. Attackers can submit spec

  • 7.5 High severity

    commonmark: Inefficient Algorithmic Complexity

    CVE-2026-86429Thephpleague

    The league/commonmark (thephpleague/commonmark) library in versions >= 1.5.0 and < 2.9.1 contains quadratic parsing complexity in its SmartPunctExtension and AttributesExtension. When either extension is explicitly registered on the Environment (they are not e

  • 7.5 High severity

    commonmark: Inefficient Algorithmic Complexity

    CVE-2026-86428Thephpleague

    commonmark versions from 1.5.0 before 2.10.0 contain a denial of service vulnerability in the AttributesExtension when processing distinctly-named attributes. Attackers can submit Markdown with numerous distinct attribute names to cause quadratic-time attribut

  • 7.5 High severity

    moos-ivp: Inefficient Algorithmic Complexity

    CVE-2026-85446Moos-ivp

    MOOS-IvP versions through 24.8.1 contain a quadratic processing vulnerability in uFldNodeComms where each new node identity creates a ledger entry and triggers all-pairs distribution work. Attackers can supply unbounded distinct node names in reports to drive

  • 7.5 High severity

    js-yaml: Uncontrolled Resource Consumption

    CVE-2026-84375Nodeca

    js-yaml is a JavaScript YAML parser and dumper. From 3.0.0 until 3.15.2, 4.3.2, and 5.4.1, maxTotalMergeKeys in lib/js-yaml/loader.js and lib/loader.js does not count empty mapping sources while processing the merge key <<. An attacker can alias a large sequen

  • 7.5 High severity

    Red Hat OpenShift Container Platform 4.13: Inefficient Algorithmic Complexity

    CVE-2026-49329Red Hat

    A flaw was found in openshift/oauth-server. The OAuth login and error page endpoints pass the unauthenticated Accept-Language header to golang.org/x/text/language.ParseAcceptLanguage() without input validation. A bypass of the CVE-2022-32149 mitigation exists:

  • 8.7 High severity

    xmldom: Uncontrolled Resource Consumption

    CVE-2026-83614Xmldom

    xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module. Prior to @xmldom/xmldom versions 0.8.15 and 0.9.12, and in xmldom versions 0.3.0 through 0.6.0, two independent quadratic paths can cause denial of servic

  • 8.7 High severity

    xmldom: Inefficient Algorithmic Complexity

    CVE-2026-83613Xmldom

    xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module. Prior to @xmldom/xmldom versions 0.8.15 and 0.9.12, and in xmldom version 0.6.0 and earlier, DOMHandler.startElement in lib/dom-parser.js inserts every pa

  • 7.5 High severity

    nltk: Inefficient Algorithmic Complexity

    CVE-2026-81722Nltk

    nltk PorterStemmer in versions <= 3.10.2 (fixed in 3.10.3) contains an inefficient-algorithmic-complexity denial of service in PorterStemmer.stem(). The _is_consonant() helper walks backward over the entire run of trailing 'y' characters on every call, and _me

  • 7.5 High severity

    Apache APISIX: Inefficient Algorithmic Complexity

    CVE-2026-75005Apache

    Inefficient Algorithmic Complexity vulnerability in Apache APISIX. A single small request can pin a gateway worker at 100% CPU for an extended period in graphql-limit-count routes. This issue affects Apache APISIX: 3.17.0. Users are recommended to upgrade to v

  • 7.5 High severity

    icalendar: Uncontrolled Resource Consumption

    CVE-2026-55099Collective

    icalendar is an RFC 5545 compatible parser and generator of iCalendar files for Python. From 7.1.0 until 7.1.3, the Component equality method in src/icalendar/cal/component.py compares nested subcomponents with two membership loops, and each membership test in

  • 7.5 High severity

    netty: Inefficient Algorithmic Complexity

    CVE-2026-75596Netty

    Netty is an asynchronous, event-driven network application framework. Prior to 4.1.137.Final and 4.2.17.Final, the default io.netty.handler.ssl.SniHandler constructors use the pre-handshake ClientHello aggregation path in handler/src/main/java/io/netty/handler

  • 7.5 High severity

    libexpat: Inefficient Algorithmic Complexity

    CVE-2026-66046Libexpat Project

    Expat through 2.8.3 contains a denial of service vulnerability caused by quadratic algorithmic complexity in the storeAtts() function in xmlparse.c, where processing N specified attributes with non-normalized values triggers an O(N^2) linear scan of elementTyp

  • 8.7 High severity

    sqlparse: Uncontrolled Resource Consumption

    CVE-2026-71491Andialbrecht

    sqlparse is a non-validating SQL parser module for Python. Prior to 0.6.0, group_comments in sqlparse/engine/grouping.py repeatedly rescans comment-only statements before the MAX_GROUPING_TOKENS guard, causing quadratic CPU consumption through sqlparse.parse()

  • 8.7 High severity

    sqlparse: Inefficient Algorithmic Complexity

    CVE-2026-54284Andialbrecht

    sqlparse is a non-validating SQL parser module for Python. Prior to 0.6.0, TokenList construction and string conversion in sqlparse/sql.py repeatedly flatten nested token subtrees constructed by group_parenthesis and group_case, causing quadratic CPU consumpti

  • 7.5 High severity

    js-yaml: Inefficient Algorithmic Complexity

    CVE-2026-73643Nodeca

    js-yaml is a JavaScript YAML parser and dumper. From 5.0.0 until 5.2.2, parsing a small YAML document can take exponential time when an application calls load() or loadAll() on untrusted input. In src/parser/parser.ts, readFlowCollection uses restoreState and

  • 7.5 High severity

    rsync: Inefficient Algorithmic Complexity

    CVE-2026-70453RsyncProject

    rsync before 3.5.0 contains an algorithmic complexity vulnerability in the hash_search() function that allows a remote attacker to cause a denial of service by delivering a carefully constructed file list. A sender can exploit the quadratic-time worst-case beh

  • 8.7 High severity

    shescape: Uncontrolled Resource Consumption

    CVE-2026-73413Ericcornelissen

    Shescape is a simple shell escape library for JavaScript. From 2.1.11 until 2.1.14 and 3.0.1, the flag-protection loop in compose in src/internal/compose.js repeatedly joins and slices flag fragments when flagProtection is enabled, which is the default, making

  • 7.5 High severity

    commonmark: Inefficient Algorithmic Complexity

    CVE-2026-71488Thephpleague

    league/commonmark is a PHP library for parsing and rendering CommonMark Markdown. From 0.6.0 until 2.9.0, specially crafted Markdown lines can cause the parser to have quadratic time complexity when converting, because several parsing paths repeatedly rescan g

  • 7.5 High severity

    html_sanitize_ex: Inefficient Algorithmic Complexity

    CVE-2026-68750Rrrene

    Inefficient Algorithmic Complexity vulnerability in the traversal engine in rrrene html_sanitize_ex allows an unauthenticated remote attacker to exhaust server CPU and memory via a flat run of sibling elements in sanitized HTML. The list clause of HtmlSanitize

  • 7.5 High severity

    nuxt: Inefficient Algorithmic Complexity

    CVE-2026-71321Nuxt

    Nuxt is an open-source web development framework for Vue.js. From 3.1.0 until 3.21.10 and 4.5.1, the internal island renderer endpoint `/__nuxt_island/...` decodes and hashes attacker-controlled JSON body input with destr and ohash before validating the URL-re

  • 7.5 High severity

    BC-JAVA: Inefficient Algorithmic Complexity

    CVE-2026-58059Legion of the Bouncy Castle

    In Bouncy Castle for Java before 1.85, Quadratic-time escaping when stringifying X.500 distinguished names. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bc-fips 1.0.2.7 (1.0.X series), 2.0.2

  • 7.5 High severity

    cJSON: Inefficient Algorithmic Complexity

    CVE-2026-67216DaveGamble

    cJSON through 1.7.19 contains an inefficient algorithmic complexity flaw in cJSON_Compare(). When comparing objects, the function recurses into each shared subtree twice, once in each direction, with no depth guard, making the running time exponential in nesti

  • 7.5 High severity

    react-router: Uncontrolled Resource Consumption

    CVE-2026-55685Remix-run

    React Router is a router for React. In versions 7.0.0 through 7.17.0, the manifest endpoint could be accessed via unauthenticated targeted requests that would put heavy load on the server and slow down response times. This issue is a follow up to CVE-2026-4234

  • 7.5 High severity

    Apache Thrift: Inefficient Algorithmic Complexity

    CVE-2026-55968ApacheEPSS 1.03%

    Inefficient Algorithmic Complexity, Allocation of Resources Without Limits or Throttling vulnerability in Apache Thrift Node.js bindings. This issue affects Apache Thrift: before 0.24.0. Users are recommended to upgrade to version 0.24.0, which fixes the issue

  • 8.7 High severity

    bandit: Inefficient Algorithmic Complexity

    CVE-2026-65623Mtrudel

    Inefficient Algorithmic Complexity vulnerability in mtrudel bandit allows unauthenticated remote denial of service via CPU exhaustion during WebSocket fragment reassembly. The size guard 'Elixir.Bandit.WebSocket.Connection':oversize_message?/2 called from hand

  • 7.5 High severity

    pyasn1: Uncontrolled Resource Consumption

    CVE-2026-59885Pyasn1

    pyasn1 is a generic ASN.1 library for Python. Prior to 0.6.4, the BER, CER, and DER decoders process OBJECT IDENTIFIER and RELATIVE-OID values in quadratic time relative to the number of arcs, so a small crafted payload containing an OID with many arcs consume

  • 8.7 High severity

    parse-server: Inefficient Algorithmic Complexity

    CVE-2026-57480Parse-community

    Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.9.1-alpha.12 and 8.6.82, deeply nested $or, $and, and $nor query condition operators in the REST API or LiveQuery query handling could trigger ex

  • 7.5 High severity

    elysia: Inefficient Algorithmic Complexity

    CVE-2026-56669Elysiajs

    Elysia is a Typescript framework for request validation, type inference, OpenAPI documentation, and client-server communication. Prior to 1.4.29, Elysia uses getAll in form data normalization for multipart/form-data endpoints, causing the amount of work to gro

  • 8.7 High severity

    py7zr: Inefficient Algorithmic Complexity

    CVE-2026-55206Miurahr

    py7zr is a Python-based library and utility to support 7zip archive compression, decompression, encryption and decryption. Prior to 1.1.3, PackInfo._read() in archiveinfo.py used an O(n^2) cumulative sum pattern for attacker-controlled numstreams values parsed

  • 7.5 High severity

    mistune: Inefficient Algorithmic Complexity

    CVE-2026-59928Lepture

    Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, a Markdown document containing many repeated or distinct reference-link definitions causes quadratic work in src/mistune/block_parser.py and the ref_links environment dictionary ha

  • 7.5 High severity

    mistune: Inefficient Algorithmic Complexity

    CVE-2026-59925Lepture

    Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, long sequences of well-formed double-asterisk or triple-asterisk emphasis pairs around a character cause quadratic work in src/mistune/inline_parser.py because the parser scans for

  • 7.5 High severity

    mistune: Inefficient Algorithmic Complexity

    CVE-2026-59922Lepture

    Mistune is a Python Markdown parser with renderers and plugins. Prior to 3.3.0, a run of closed tilde, equals-sign, or caret marker pairs around a character causes quadratic work in src/mistune/plugins/formatting.py when the strikethrough, mark, or insert plug

  • 7.5 High severity

    linkify-it: Inefficient Algorithmic Complexity

    CVE-2026-59887Markdown-it

    linkify-it is a links recognition library with full Unicode support. Prior to 5.0.2, the mailto: schema validator used by .test() and .match() can be invoked at every mailto: occurrence and scan the remaining input through src_email_name in lib/re.mjs, causing

  • 7.5 High severity

    immutable-js: Inefficient Algorithmic Complexity

    CVE-2026-59880Immutable-js

    Immutable.js provides many Persistent Immutable data structures. Prior to 4.3.9 and 5.1.8, Immutable.Map and Immutable.Set keep keys that share the same 32-bit hash in a HashCollisionNode collision bucket that is scanned linearly, allowing an attacker who cont

  • 7.5 High severity

    js-yaml: Allocation of Resources Without Limits or Throttling

    CVE-2026-59870Nodeca

    js-yaml is a JavaScript YAML parser and dumper. Prior to 3.15.1, 4.3.1, and 5.2.1, YAML11_SCHEMA support for the !!omap tag in src/tag/sequence/omap.ts uses omapTag.addItem() to perform a linear duplicate-key scan on every insertion, causing O(n^2) CPU consump

  • 7.5 High severity

    js-yaml: Inefficient Algorithmic Complexity

    CVE-2026-59869Nodeca

    js-yaml is a JavaScript YAML parser and dumper. From 3.0.0 before 3.15.0 and from 4.0.0 before 4.3.0, js-yaml can spend quadratic CPU time parsing a document whose size grows only linearly when a chain of mappings uses merge keys where each mapping merges the

  • 7.5 High severity

    js-yaml: Allocation of Resources Without Limits or Throttling

    CVE-2026-59868Nodeca

    js-yaml is a JavaScript YAML parser and dumper. From 5.0.0 before 5.2.0, when merge keys are enabled, js-yaml can spend quadratic CPU time parsing a document whose size grows only linearly when a chain of mappings uses merge keys where each mapping merges the