{"answers":{"affected":"3 open source packages ship an affected version, including nltk. It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-81725 in the wild and no public exploit code.","fix":"Upgrade nltk to 3.10.3 or later.","what":"CVE-2026-81725 is a medium-severity denial of service vulnerability in nltk, published on 27 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2026-81725 and fix it if it is affected.\n\nWhat it is: CVE-2026-81725 is a medium-severity denial of service vulnerability in nltk, published on 27 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2026-81725 in the wild and no public exploit code.\n\nAffected packages and fixed versions:\n- nltk (PyPI): affected all versions; fixed in 3.10.3\n- nltk (PyPI): affected all versions; fixed in 3.10.3\n- nltk (PyPI): affected all versions; fixed in 3.10.3\n\nTask:\n1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.\n2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.\n3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.\n4. Run the tests and summarise what changed and why.\n5. If nothing in the project is affected, say so and change nothing.\n\nReference: https://insights.sbomify.com/CVE-2026-81725/ (Markdown: https://insights.sbomify.com/CVE-2026-81725/index.md)","id":"CVE-2026-81725","markdown":"https://insights.sbomify.com/CVE-2026-81725/index.md","name":"CVE-2026-81725","record":{"aliases":["DEBIAN-CVE-2026-81725","ECHO-c4c0-fd69-5811","GHSA-8mpw-7fpc-4gqj","MINI-v5qj-7q8q-jhfc","PYSEC-2026-3752","UBUNTU-CVE-2026-81725"],"analysis":{"component_type":"library","fix_type":"upgrade","impacts":["denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Python NLP library","requires_auth":"none","summary":"Attackers can cause denial of service in NLTK by supplying malformed TEI blocks that trigger quadratic CPU consumption via regex patterns.","user_interaction":"not_required","vuln_class":"denial_of_service"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"VulnCheck","cpe":[{"product":"nltk","vendor":"nltk"}],"cvss":{"score":6.3,"severity":"medium","source":"cna","vector":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","version":"4.0"},"cwes":[{"id":"CWE-400","name":"Uncontrolled Resource Consumption"}],"description":"NLTK before 3.10.3 contains a regular expression denial of service vulnerability in Pl196xCorpusReader that allows attackers to cause quadratic CPU consumption by supplying malformed TEI blocks with many unmatched opening tags. Attackers can exploit lazy regex patterns in the read_block method through public APIs like words() and tagged_words() to force repeated rescans and achieve near-quadratic runtime growth.","ecosystems":["PyPI"],"exploits":{"exploitdb":0,"first_seen":null,"github_poc":0,"max_poc_stars":null,"metasploit":0,"nuclei":0,"refs":[],"tier":"none_known"},"has_fix":true,"headline":"NLTK before 3.10.3 Regular Expression Denial of Service via Pl196xCorpusReader","id":"CVE-2026-81725","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":"PyPI","product":null,"products":[],"type":"denial_of_service","year":"2026"},"n_packages":3,"n_references":2,"next":{"headline":"NLTK through 3.10.3 Path Traversal via Model-Artifact APIs","id":"CVE-2026-81726"},"packages":[{"ecosystem":"PyPI","fixed":["3.10.3"],"introduced":["0"],"last_affected":[],"package":"nltk","purl":null,"source":"GHSA-8mpw-7fpc-4gqj"},{"ecosystem":"PyPI","fixed":["3.10.3"],"introduced":["0"],"last_affected":[],"package":"nltk","purl":"pkg:pypi/nltk","source":"GHSA-8mpw-7fpc-4gqj"},{"ecosystem":"PyPI","fixed":["3.10.3"],"introduced":["0"],"last_affected":[],"package":"nltk","purl":"pkg:pypi/nltk","source":"PYSEC-2026-3752"}],"prev":{"headline":"NLTK before 3.10.3 Denial of Service via Uncontrolled Recursion","id":"CVE-2026-81724"},"products":["nltk"],"published":"2026-08-27","related":[{"cvss_score":10,"headline":"Arbitrary Code Execution in NLTK StanfordSegmenter via Untrusted JAR Loading","id":"CVE-2026-0848","kev_date_added":null,"published":"2026-03-05"},{"cvss_score":10,"headline":"Zip Slip Vulnerability in nltk/nltk Leading to Remote Code Execution","id":"CVE-2025-14009","kev_date_added":null,"published":"2026-02-18"},{"cvss_score":9.4,"headline":"NLTK before 3.10.0 Remote Code Execution via Unsafe Pickle Deserialization","id":"CVE-2026-78683","kev_date_added":null,"published":"2026-08-25"},{"cvss_score":9.3,"headline":"NLTK before 3.10.3 Remote Code Execution via Unsafe Pickle Deserialization","id":"CVE-2026-79657","kev_date_added":null,"published":"2026-08-25"},{"cvss_score":9.3,"headline":"NLTK before 3.10.3 JVM Argument Injection via Per-Call Options","id":"CVE-2026-79675","kev_date_added":null,"published":"2026-08-25"},{"cvss_score":8.8,"headline":"NLTK 3.10.2 Path Traversal via corpus-reader constructors","id":"CVE-2026-79674","kev_date_added":null,"published":"2026-08-25"},{"cvss_score":8.7,"headline":"nltk PorterStemmer before 3.10.3 Quadratic-time DoS","id":"CVE-2026-81722","kev_date_added":null,"published":"2026-08-27"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CC BY 4.0","name":"GitHub Advisory Database","prefix":"GHSA"},{"class":"attribution","licence":"CC BY 4.0","name":"PyPA Advisory Database","prefix":"PYSEC"},{"class":"attribution","licence":"US public information, NVD API terms","name":"NVD"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"no","exploitation":"none","technical_impact":"partial"},"state":"PUBLISHED","updated":"2026-08-28","vendors":["nltk"]},"summary":"Attackers can cause denial of service in NLTK by supplying malformed TEI blocks that trigger quadratic CPU consumption via regex patterns.","url":"https://insights.sbomify.com/CVE-2026-81725/"}