{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-90339 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-90339 is a vulnerability in Linux, published on 17 Sep 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-2026-90339 and fix it if it is affected.\n\nWhat it is: CVE-2026-90339 is a vulnerability in Linux, published on 17 Sep 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-2026-90339 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-2026-90339/ (Markdown: https://insights.sbomify.com/CVE-2026-90339/index.md)","id":"CVE-2026-90339","markdown":"https://insights.sbomify.com/CVE-2026-90339/index.md","name":"CVE-2026-90339","record":{"aliases":["GHSA-qfw2-5x2v-5xgv","UBUNTU-CVE-2026-90339"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["security_bypass"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel","requires_auth":"none","summary":"A flaw in the Linux kernel PowerPC syscall handling allows bypassing seccomp or ptrace restrictions, potentially enabling unauthorized system call execution.","user_interaction":"not_required","vuln_class":"security_feature_bypass"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":null,"severity":null,"source":null,"vector":null,"version":null},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/syscall: Fix syscall skip handling for seccomp and ptrace\n\nAfter enabling GENERIC_ENTRY on PowerPC, syscall_enter_from_user_mode()\nreturns -1 as a sentinel to signal that seccomp or ptrace has intercepted\nthe syscall and already set a return value via syscall_set_return_value().\nsystem_call_exception() was not handling this sentinel, and since -1UL\nis \u003e= NR_syscalls, the code fell into the out-of-range path and returned\n-ENOSYS, overwriting the errno already placed in regs-\u003egpr[3].\n\nThe naive fix of checking r0 == -1L before the NR_syscalls bounds check\nis ambiguous: a user legitimately calling syscall(-1) also produces r0 ==\n-1L, and a tracer intercepting such a call would have its injected return\nvalue silently discarded.\n\nFix this by introducing a thread flag that is set whenever\nsyscall_set_return_value() explicitly updates the return value. In\nsystem_call_exception(), check and clear this flag before dispatching\nthe syscall, and return the preset value directly when it is present.\nThis ensures that an explicitly supplied return value always suppresses\nsyscall execution, regardless of the syscall number.\n\nThis handles all seccomp actions correctly:\n\n  - SECCOMP_RET_ERRNO, SECCOMP_RET_TRACE (no tracer), SECCOMP_RET_USER_NOTIF:\n    all call syscall_set_return_value(), flag is set, injected value returned.\n  - SECCOMP_RET_TRAP, SECCOMP_RET_KILL: call syscall_rollback() and deliver\n    a signal; flag is not set, but the process is dying so the return value\n    is irrelevant.\n\nThe fix covers both ppc32 and ppc64 with no #ifdefs.","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":"powerpc/syscall: Fix syscall skip handling for seccomp and ptrace","id":"CVE-2026-90339","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"security_feature_bypass","year":"2026"},"n_packages":0,"n_references":2,"next":{"headline":"pinctrl: generic: free maps on pinctrl_generic_to_map() failure","id":"CVE-2026-90340"},"packages":[],"prev":{"headline":"serial: amba-pl011: keep console clock enabled for atomic writes","id":"CVE-2026-90338"},"products":["Linux"],"published":"2026-09-17","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-10-19","vendors":["Linux"]},"summary":"A flaw in the Linux kernel PowerPC syscall handling allows bypassing seccomp or ptrace restrictions, potentially enabling unauthorized system call execution.","url":"https://insights.sbomify.com/CVE-2026-90339/"}