CVE-2026-53550 js-yaml: Quadratic-complexity DoS in merge key handling via repeated aliases

js-yaml is a JavaScript YAML parser and dumper. Prior to 4.2.0 and 3.15.0, a crafted YAML document can trigger algorithmic CPU exhaustion in js-yaml merge-key processing by repeating the same alias many times in a merge sequence. This causes quadratic parse-time behavior relative to input size an...

CVE-2026-53550 js-yaml: Quadratic-complexity DoS in merge key handling via repeated aliases

js-yaml is a JavaScript YAML parser and dumper. Prior to 4.2.0 and 3.15.0, a crafted YAML document can trigger algorithmic CPU exhaustion in js-yaml merge-key processing by repeating the same alias many times in a merge sequence. This causes quadratic parse-time behavior relative to input size an...

CVE-2026-53550

js-yaml vulnerability CVE-2026-53550 stems from the merge-key handling (<<) in lib/loader.js, causing quadratic parse-time DoS when processing crafted YAML with repeated aliases prior to version 4.2.0. Affected: js-yaml

GHSA-H4GH-22QQ-72R7 py7zr: O(n^2) algorithmic complexity DoS in PackInfo._read()

Summary PackInfo.read uses an On^2 cumulative sum pattern where numstreams is read directly from the archive header. A crafted .7z archive with a large numstreams value causes excessive CPU consumption during SevenZipFile.init — no extraction is needed. A 50 KB archive takes 7 seconds of CPU time...

py7zr: O(n^2) algorithmic complexity DoS in PackInfo._read()

Summary PackInfo.read uses an On^2 cumulative sum pattern where numstreams is read directly from the archive header. A crafted .7z archive with a large numstreams value causes excessive CPU consumption during SevenZipFile.init — no extraction is needed. A 50 KB archive takes 7 seconds of CPU time...

CVE-2026-49293 CPU exhaustion via O(n^2) BigInt construction on radix-prefixed integer literals

js-toml is a TOML parser for JavaScript, fully compliant with the TOML 1.0.0 Spec. Versions up to and including 1.1.0 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...

CVE-2026-49293 CPU exhaustion via O(n^2) BigInt construction on radix-prefixed integer literals

js-toml is a TOML parser for JavaScript, fully compliant with the TOML 1.0.0 Spec. Versions up to and including 1.1.0 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...

PT-2026-51098

Name of the Vulnerable Software and Affected Versions py7zr versions prior to 1.1.3 Description A denial of service issue exists where a crafted .7z archive with a large numstreams value causes excessive CPU consumption. This occurs because the PackInfo. read function in archiveinfo.py uses an On...

markdown-it: Quadratic complexity DoS in smartquotes rule via replaceAt string operations

Summary A quadratic time complexity vulnerability exists in markdown-it's smartquotes rule enabled via the typographer: true option. An attacker can craft a markdown input consisting of consecutive quotation marks that causes the parser to consume excessive CPU time, leading to denial of service...

NPM: JS-YAML: Quadratic-complexity DoS in merge key handling via repeated aliases

NPM: JS-YAML: Quadratic-complexity DoS in merge key handling via repeated aliases vulnerability discovered by ? in WordPress Npm js-yaml versions = 4.1.1...

PT-2026-49571

Name of the Vulnerable Software and Affected Versions python-multipart versions prior to 0.0.30 Description A quadratic complexity issue exists when parsing application/x-www-form-urlencoded bodies. The QuerystringParser performs a two-step lookup for field separators, scanning the entire remaini...

PT-2026-49555

Name of the Vulnerable Software and Affected Versions markdown-it affected versions not specified Description A quadratic time complexity issue exists in the smartquotes rule when the typographer: true option is enabled. An attacker can provide markdown input containing a large number of...

CVE-2026-43967

Inefficient Algorithmic Complexity vulnerability in absinthe-graphql absinthe allows unauthenticated denial of service via quadratic fragment-name uniqueness validation. 'Elixir.Absinthe.Phase.Document.Validation.UniqueFragmentNames':run/2 iterates over all fragments and for each one calls...

BIT-PYTHON-2026-3276 Potential DoS via quadratic complexity in unicodedata.normalize()

unicodedata.normalize can take excessive CPU time when processing specially crafted Unicode input containing long runs of combining characters with alternating Canonical Combining Class values. This affects all normalization forms...

Quadratic complexity in WordDecoder.DecodeHeader in mime

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CVE-2026-3276 Potential DoS via quadratic complexity in unicodedata.normalize()

unicodedata.normalize can take excessive CPU time when processing specially crafted Unicode input containing long runs of combining characters with alternating Canonical Combining Class values. This affects all normalization forms...

CVE-2026-3276

The CVE concerns Python’s unicodedata.normalize() taking excessive CPU time when given specially crafted Unicode input with long runs of combining characters that have alternating Canonical Combining Class (CCC) values. Affected: the normalize() function across all normalization forms. Root cause...

CVE-2026-42504 Quadratic complexity in WordDecoder.DecodeHeader in mime

Decoding a maliciously-crafted MIME header containing many invalid encoded-words can consume excessive CPU...

CVE-2026-27145

CVE-2026-27145 is reported in IBM Operator for PostgreSQL security bulletin for versions v28.3.0–v28.3.1. Description: the function (*x509.Certificate).VerifyHostname previously called matchHostnames in a loop over all DNS SAN entries, causing repeated string splits on the same hostname and quadr...

CVE-2026-27145

x509.Certificate.VerifyHostname previously called matchHostnames in a loop over all DNS Subject Alternative Name SAN entries. This caused strings.Splithost, "." to execute repeatedly on the same input hostname. With a large DNS SAN list, verification costs scaled quadratically based on the number...