{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-53239 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-53239 is a high-severity use after free vulnerability in Linux kernel, published on 25 Jun 2026. 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-2026-53239 and fix it if it is affected.\n\nWhat it is: CVE-2026-53239 is a high-severity use after free vulnerability in Linux kernel, published on 25 Jun 2026. 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-2026-53239 in the wild and no public exploit code.\n\nAffected product: Linux kernel. 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-2026-53239/ (Markdown: https://insights.sbomify.com/CVE-2026-53239/index.md)","id":"CVE-2026-53239","markdown":"https://insights.sbomify.com/CVE-2026-53239/index.md","name":"CVE-2026-53239","record":{"aliases":["AZL-90842","BELL-CVE-2026-53239","DEBIAN-CVE-2026-53239","GHSA-qmj7-fh92-4787","ROOT-OS-DEBIAN-11-CVE-2026-53239","ROOT-OS-DEBIAN-12-CVE-2026-53239","ROOT-OS-UBUNTU-2204-CVE-2026-53239","ROOT-OS-UBUNTU-2404-CVE-2026-53239","UBUNTU-CVE-2026-53239"],"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 race condition in the Linux kernel's xfrm policy handling allows a use-after-free, potentially enabling local attackers to 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":"linux_kernel","vendor":"linux"}],"cvss":{"score":7.8,"severity":"high","source":"cna","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"},{"id":"CWE-362","name":"Concurrent Execution using Shared Resource with Improper Synchronization"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: policy: fix use-after-free on inexact bin in xfrm_policy_bysel_ctx()\n\nFix the race by pruning the bin while still holding xfrm_policy_lock,\nbefore dropping it. Use __xfrm_policy_inexact_prune_bin() directly since\nthe lock is already held. The wrapper xfrm_policy_inexact_prune_bin()\nbecomes unused and is removed.\n\nRace:\n\n  CPU0 (XFRM_MSG_DELPOLICY)           CPU1 (XFRM_MSG_NEWSPDINFO)\n  ==========================          ==========================\n  xfrm_policy_bysel_ctx():\n    spin_lock_bh(xfrm_policy_lock)\n    bin = xfrm_policy_inexact_lookup()\n    __xfrm_policy_unlink(pol)\n    spin_unlock_bh(xfrm_policy_lock)\n    xfrm_policy_kill(ret)\n    // wide window, lock not held\n                                       xfrm_hash_rebuild():\n                                         spin_lock_bh(xfrm_policy_lock)\n                                         __xfrm_policy_inexact_flush():\n                                           kfree_rcu(bin)  // bin freed\n                                         spin_unlock_bh(xfrm_policy_lock)\n    xfrm_policy_inexact_prune_bin(bin)\n    // UAF: bin is freed","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":"xfrm: policy: fix use-after-free on inexact bin in xfrm_policy_bysel_ctx()","id":"CVE-2026-53239","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"use_after_free","year":"2026"},"n_packages":0,"n_references":8,"next":{"headline":"xfrm: iptfs: fix use-after-free on first_skb in __input_process_payload","id":"CVE-2026-53240"},"packages":[],"prev":{"headline":"netlabel: validate unlabeled address and mask attribute lengths","id":"CVE-2026-53238"},"products":["Linux"],"published":"2026-06-25","related":[{"cvss_score":8.8,"headline":"Linux Kernel Out-of-Bounds Write","id":"CVE-2026-53266","kev_date_added":"2026-09-18","published":"2026-06-25"},{"cvss_score":8.8,"headline":"Linux Kernel Improper Input Validation","id":"CVE-2013-6282","kev_date_added":"2022-09-15","published":"2013-11-19"},{"cvss_score":8.4,"headline":"Linux Kernel Heap-Based Buffer Overflow","id":"CVE-2022-0185","kev_date_added":"2024-08-21","published":"2022-02-11"},{"cvss_score":8.4,"headline":"Linux Kernel Privilege Escalation","id":"CVE-2013-2094","kev_date_added":"2022-09-15","published":"2013-05-14"},{"cvss_score":7.8,"headline":"Linux Kernel Unspecified","id":"CVE-2026-53362","kev_date_added":"2026-08-27","published":"2026-07-04"},{"cvss_score":7.8,"headline":"Linux Kernel Missing Initialization of a Variable","id":"CVE-2026-46300","kev_date_added":"2026-10-28","published":"2026-05-23"},{"cvss_score":7.8,"headline":"Linux Kernel Race Condition","id":"CVE-2025-39964","kev_date_added":"2026-09-18","published":"2025-10-13"}],"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":"no","exploitation":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-10-19","vendors":["Linux"]},"summary":"A race condition in the Linux kernel's xfrm policy handling allows a use-after-free, potentially enabling local attackers to execute code or escalate privileges.","url":"https://insights.sbomify.com/CVE-2026-53239/"}