CVE-2026-84375: falha de alta gravidade em nodeca js-yaml
js-yaml: maxTotalMergeKeys does not limit CPU use for empty merge sources
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21Vexday Risk Score
Sem sinal de exploração. Nenhum artefato público de exploração conhecido até agora.
ssvc Trackcvss 7.5epss 0.5%
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 sequence of empty mappings into many merge targets, causing O(N * K) processing while totalMergeKeys remains unchanged and the configured resource limit is never reached. A relatively small YAML document can therefore cause prolonged CPU consumption in applications that parse untrusted YAML, and merge processing is enabled by default on these release lines. In v3 & v4, merge is enabled by default so the severity score is higher. This issue is fixed in versions 3.15.2, 4.3.2, and 5.4.1.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Produtos afetados
nodeca · js-yamlCVEs relacionadas — nodeca js-yaml
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Referências
https://github.com/nodeca/js-yaml/commit/3485bc06ff8a0251505f44a00414d90df2466639https://github.com/nodeca/js-yaml/commit/6a8e05f9a485188ed730ac81e81ae221352ef480https://github.com/nodeca/js-yaml/commit/d90b6612a5a84385bdcb556c44578eac76dc0f6bhttps://github.com/nodeca/js-yaml/pull/797https://github.com/nodeca/js-yaml/releases/tag/3.15.2https://github.com/nodeca/js-yaml/releases/tag/4.3.2https://github.com/nodeca/js-yaml/releases/tag/5.4.1https://github.com/nodeca/js-yaml/security/advisories/GHSA-2883-xcg3-v3hh