{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-72020 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-72020 is a critical vulnerability in Linux, published on 15 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-2026-72020 and fix it if it is affected.\n\nWhat it is: CVE-2026-72020 is a critical vulnerability in Linux, published on 15 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-2026-72020 in the wild and no public exploit code.\n\nAffected product: 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-2026-72020/ (Markdown: https://insights.sbomify.com/CVE-2026-72020/index.md)","id":"CVE-2026-72020","markdown":"https://insights.sbomify.com/CVE-2026-72020/index.md","name":"CVE-2026-72020","record":{"aliases":["BELL-CVE-2026-72020","DEBIAN-CVE-2026-72020","GHSA-phwq-3c7h-j8x3","UBUNTU-CVE-2026-72020"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["data_read","denial_of_service"],"network_reachable":"yes","non_default_config":false,"product_category":"Linux kernel IPVS","requires_auth":"none","summary":"Attackers can leak stale kernel memory via TCP sequence numbers or corrupt traffic in Linux IPVS when processing malformed sync messages.","user_interaction":"not_required","vuln_class":"information_disclosure"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":9.8,"severity":"critical","source":"cna","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"cwes":[{"id":"CWE-457","name":"Use of Uninitialized Variable"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nipvs: reset full ip_vs_seq structs in ip_vs_conn_new\n\nCommit 9a05475cebdd (\"ipvs: avoid kmem_cache_zalloc in\nip_vs_conn_new\") changed ip_vs_conn_new() to allocate an ip_vs_conn\nobject with kmem_cache_alloc().  The function then initializes many\nfields explicitly, but only resets in_seq.delta and out_seq.delta in the\ntwo struct ip_vs_seq members.\n\nThat leaves init_seq and previous_delta uninitialized.  This is normally\nharmless while the corresponding IP_VS_CONN_F_IN_SEQ or\nIP_VS_CONN_F_OUT_SEQ flag is clear.  For connections learned from a sync\nmessage, however, ip_vs_proc_conn() preserves those flags from\nIP_VS_CONN_F_BACKUP_MASK and passes opt=NULL when the message omits\nIPVS_OPT_SEQ_DATA.  In that case the new connection can be hashed with\nSEQ flags set but with the rest of in_seq/out_seq still containing stale\nslab data.\n\nWhen a packet for such a connection is later handled by an IPVS\napplication helper, vs_fix_seq() and vs_fix_ack_seq() use\nprevious_delta and init_seq to rewrite TCP sequence numbers.  A malformed\nsync message can therefore make forwarded packets carry stale slab bytes\nin their TCP seq/ack numbers, and can also corrupt the forwarded TCP\nflow.\n\nReset both struct ip_vs_seq members completely before publishing the\nconnection.  This matches the existing \"reset struct ip_vs_seq\" comment\nand keeps the sequence-adjustment gates inactive unless valid sequence\ndata is installed later.","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":"ipvs: reset full ip_vs_seq structs in ip_vs_conn_new","id":"CVE-2026-72020","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"information_disclosure","year":"2026"},"n_packages":0,"n_references":8,"next":{"headline":"ipvs: use parsed transport offset in SCTP state lookup","id":"CVE-2026-72021"},"packages":[],"prev":{"headline":"macsec: don't read an unset MAC header in macsec_encrypt()","id":"CVE-2026-72019"},"products":["Linux"],"published":"2026-08-15","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"CWE Terms of Use","name":"CWE (MITRE)"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":"yes","exploitation":"none","technical_impact":"total"},"state":"PUBLISHED","updated":"2026-10-19","vendors":["Linux"]},"summary":"Attackers can leak stale kernel memory via TCP sequence numbers or corrupt traffic in Linux IPVS when processing malformed sync messages.","url":"https://insights.sbomify.com/CVE-2026-72020/"}