{"answers":{"affected":"It affects 2 products.","exploited":"There is no known exploitation of CVE-2025-39877 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2025-39877 is a high-severity use after free vulnerability in Debian Debian Linux, published on 23 Sep 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-2025-39877 and fix it if it is affected.\n\nWhat it is: CVE-2025-39877 is a high-severity use after free vulnerability in Debian Debian Linux, published on 23 Sep 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-2025-39877 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-2025-39877/ (Markdown: https://insights.sbomify.com/CVE-2025-39877/index.md)","id":"CVE-2025-39877","markdown":"https://insights.sbomify.com/CVE-2025-39877/index.md","name":"CVE-2025-39877","record":{"aliases":["BELL-CVE-2025-39877","DEBIAN-CVE-2025-39877","GHSA-46f8-9r54-mw7h","ROOT-OS-UBUNTU-2204-CVE-2025-39877","ROOT-OS-UBUNTU-2404-CVE-2025-39877","UBUNTU-CVE-2025-39877"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["code_execution","privilege_escalation"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"low_privilege","summary":"A use-after-free race condition in the Linux kernel DAMON sysfs interface allows attackers to potentially execute code or escalate privileges.","user_interaction":"not_required","vuln_class":"use_after_free"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"debian_linux","vendor":"debian"},{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":7.8,"severity":"high","source":"nvd","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-416","name":"Use After Free"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmm/damon/sysfs: fix use-after-free in state_show()\n\nstate_show() reads kdamond-\u003edamon_ctx without holding damon_sysfs_lock. \nThis allows a use-after-free race:\n\nCPU 0                         CPU 1\n-----                         -----\nstate_show()                  damon_sysfs_turn_damon_on()\nctx = kdamond-\u003edamon_ctx;     mutex_lock(\u0026damon_sysfs_lock);\n                              damon_destroy_ctx(kdamond-\u003edamon_ctx);\n                              kdamond-\u003edamon_ctx = NULL;\n                              mutex_unlock(\u0026damon_sysfs_lock);\ndamon_is_running(ctx);        /* ctx is freed */\nmutex_lock(\u0026ctx-\u003ekdamond_lock); /* UAF */\n\n(The race can also occur with damon_sysfs_kdamonds_rm_dirs() and\ndamon_sysfs_kdamond_release(), which free or replace the context under\ndamon_sysfs_lock.)\n\nFix by taking damon_sysfs_lock before dereferencing the context, mirroring\nthe locking used in pid_show().\n\nThe bug has existed since state_show() first accessed kdamond-\u003edamon_ctx.","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":"mm/damon/sysfs: fix use-after-free in state_show()","id":"CVE-2025-39877","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"debian:debian_linux","products":["debian:debian_linux","linux:linux_kernel"],"type":"use_after_free","year":"2025"},"n_packages":0,"n_references":5,"next":{"headline":"ceph: fix crash after fscrypt_encrypt_pagecache_blocks() error","id":"CVE-2025-39878"},"packages":[],"prev":{"headline":"net: fec: Fix possible NPD in fec_enet_phy_reset_after_clk_enable()","id":"CVE-2025-39876"},"products":["Linux"],"published":"2025-09-23","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 use-after-free race condition in the Linux kernel DAMON sysfs interface allows attackers to potentially execute code or escalate privileges.","url":"https://insights.sbomify.com/CVE-2025-39877/"}