{"id":"CVE-2025-3262","aliases":["GHSA-489j-g2vx-39wf","PYSEC-2026-1979"],"title":"Transformers vulnerable to ReDoS attack through its SETTING_RE variable","summary":"Transformers vulnerable to ReDoS attack through its SETTING_RE variable","severity":"medium","cvss":5.3,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","vendor":"transformers","product":"transformers","ecosystem":"pip","affected":["transformers >= 4.49.0, < 4.51.0"],"patched":["transformers 4.51.0"],"published":"2025-07-07","updated":"2026-07-07","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-489j-g2vx-39wf","references":[{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-3262"},{"url":"https://github.com/huggingface/transformers/commit/0720e206c6ba28887e4d60ef60a6a089f6c1cc76"},{"url":"https://github.com/huggingface/transformers/commit/126abe3461762e5fc180e7e614391d1b4ab051ca"},{"url":"https://github.com/huggingface/transformers"},{"url":"https://huntr.com/bounties/ecf5ccc4-39e7-4fb3-b547-14a41d31a184"}],"tags":["osv","pip"],"epss":0.00434,"epssPercentile":0.37048,"ingestedAt":"2026-07-08T18:25:45.289Z","slug":"CVE-2025-3262","body":"## Overview\n\nA Regular Expression Denial of Service (ReDoS) vulnerability was discovered in the huggingface/transformers repository, specifically in version 4.49.0. The vulnerability is due to inefficient regular expression complexity in the `SETTING_RE` variable within the `transformers/commands/chat.py` file. The regex contains repetition groups and non-optimized quantifiers, leading to exponential backtracking when processing 'almost matching' payloads. This can degrade application performance and potentially result in a denial-of-service (DoS) when handling specially crafted input strings. The issue is fixed in version 4.51.0.\n\n## Affected packages\n\n- `transformers >= 4.49.0, < 4.51.0`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `transformers 4.51.0`","depth":"sunlit","depthScore":29,"depthScoreParts":{"impact":29.2,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}