{"answers":{"affected":"It affects 2 products.","exploited":"There is no known exploitation of CVE-2025-37953 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-37953 is a medium-severity vulnerability in Debian Debian Linux, published on 20 May 2025. It can only be exploited from the same machine or local network, with no action from the victim."},"fix_prompt":"Check this codebase for CVE-2025-37953 and fix it if it is affected.\n\nWhat it is: CVE-2025-37953 is a medium-severity vulnerability in Debian Debian Linux, published on 20 May 2025. It can only be exploited from the same machine or local network, with no action from the victim.\nExploitation: There is no known exploitation of CVE-2025-37953 in the wild and no public exploit code.\n\nAffected product: Debian Debian Linux. No package-level version data is available, so check the vendor advisory linked from the reference page.\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-2025-37953/ (Markdown: https://insights.sbomify.com/CVE-2025-37953/index.md)","id":"CVE-2025-37953","markdown":"https://insights.sbomify.com/CVE-2025-37953/index.md","name":"CVE-2025-37953","record":{"aliases":["BELL-CVE-2025-37953","DEBIAN-CVE-2025-37953","GHSA-ccmh-pfgg-525g","ROOT-OS-DEBIAN-12-CVE-2025-37953","UBUNTU-CVE-2025-37953"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A NULL pointer dereference in the Linux kernel's HTB scheduler can cause a system crash, requiring a kernel patch to fix.","user_interaction":"not_required","vuln_class":"null_dereference"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"debian_linux","vendor":"debian"},{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":5.5,"severity":"medium","source":"nvd","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-476","name":"NULL Pointer Dereference"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nsch_htb: make htb_deactivate() idempotent\n\nAlan reported a NULL pointer dereference in htb_next_rb_node()\nafter we made htb_qlen_notify() idempotent.\n\nIt turns out in the following case it introduced some regression:\n\nhtb_dequeue_tree():\n  |-\u003e fq_codel_dequeue()\n    |-\u003e qdisc_tree_reduce_backlog()\n      |-\u003e htb_qlen_notify()\n        |-\u003e htb_deactivate()\n  |-\u003e htb_next_rb_node()\n  |-\u003e htb_deactivate()\n\nFor htb_next_rb_node(), after calling the 1st htb_deactivate(), the\nclprio[prio]-\u003eptr could be already set to  NULL, which means\nhtb_next_rb_node() is vulnerable here.\n\nFor htb_deactivate(), although we checked qlen before calling it, in\ncase of qlen==0 after qdisc_tree_reduce_backlog(), we may call it again\nwhich triggers the warning inside.\n\nTo fix the issues here, we need to:\n\n1) Make htb_deactivate() idempotent, that is, simply return if we\n   already call it before.\n2) Make htb_next_rb_node() safe against ptr==NULL.\n\nMany thanks to Alan for testing and for the reproducer.","ecosystems":[],"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":"sch_htb: make htb_deactivate() idempotent","id":"CVE-2025-37953","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"debian:debian_linux","products":["debian:debian_linux","linux:linux_kernel"],"type":"null_dereference","year":"2025"},"n_packages":0,"n_references":8,"next":{"headline":"smb: client: Avoid race in open_cached_dir with lease breaks","id":"CVE-2025-37954"},"packages":[],"prev":{"headline":"ksmbd: Fix UAF in __close_file_table_ids","id":"CVE-2025-37952"},"products":["Linux"],"published":"2025-05-20","related":[{"cvss_score":10,"headline":"ProFTPD Improper Access Control","id":"CVE-2015-3306","kev_date_added":"2026-10-08","published":"2015-05-18"},{"cvss_score":9.9,"headline":"RoundCube Webmail Deserialization of Untrusted Data","id":"CVE-2025-49113","kev_date_added":"2026-02-20","published":"2025-06-02"},{"cvss_score":9.8,"headline":"GNU InetUtils Argument Injection","id":"CVE-2026-24061","kev_date_added":"2026-01-26","published":"2026-01-21"},{"cvss_score":9.8,"headline":"Linux Kernel Improper Check for Unusual or Exceptional Conditions","id":"CVE-2025-39682","kev_date_added":"2026-09-18","published":"2025-09-05"},{"cvss_score":9.8,"headline":"Mozilla Firefox Use-After-Free","id":"CVE-2024-9680","kev_date_added":"2024-10-15","published":"2024-10-09"},{"cvss_score":9.8,"headline":"RARLAB UnRAR Directory Traversal","id":"CVE-2022-30333","kev_date_added":"2022-08-09","published":"2022-05-09"},{"cvss_score":9.8,"headline":"Roundcube Webmail SQL Injection","id":"CVE-2021-44026","kev_date_added":"2023-06-22","published":"2021-11-19"}],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"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":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-05-11","vendors":["Linux"]},"summary":"A NULL pointer dereference in the Linux kernel's HTB scheduler can cause a system crash, requiring a kernel patch to fix.","url":"https://insights.sbomify.com/CVE-2025-37953/"}