{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-90136 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-90136 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-2026-90136 and fix it if it is affected.\n\nWhat it is: CVE-2026-90136 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-2026-90136 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-2026-90136/ (Markdown: https://insights.sbomify.com/CVE-2026-90136/index.md)","id":"CVE-2026-90136","markdown":"https://insights.sbomify.com/CVE-2026-90136/index.md","name":"CVE-2026-90136","record":{"aliases":["BELL-CVE-2026-90136","DEBIAN-CVE-2026-90136","GHSA-547r-p462-qv3c","UBUNTU-CVE-2026-90136"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service","other"],"network_reachable":"adjacent_or_local","non_default_config":false,"product_category":"Linux kernel driver","requires_auth":"high_privilege","summary":"A local attacker with root privileges can write negative values to the AMD HSMP power cap, causing an integer overflow that sends invalid multi-gigawatt limits to the SMU.","user_interaction":"not_required","vuln_class":"integer_overflow"},"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\nplatform/x86/amd/hsmp: Reject negative power cap writes in hwmon\n\nhsmp_hwmon_write() takes the user-supplied hwmon value as a signed long\nand assigns \"val / MICROWATT_PER_MILLIWATT\" to msg.args[0], which is a\n__u32.  MICROWATT_PER_MILLIWATT is an unsigned long, so a negative write\nto power1_cap (e.g. \"echo -1 \u003e power1_cap\") is first converted to a huge\nunsigned value by the division and then stored into the u32 argument.\n\nAs a result a nonsensical, multi-gigawatt socket power limit is sent to\nthe SMU via HSMP_SET_SOCKET_POWER_LIMIT instead of the write being\nrejected.\n\nReject negative values with -EINVAL before the conversion.\n\nTested with HSMP enabled:\n\n  CAP=$(dirname $(grep -l amd_hsmp_hwmon \\\n        /sys/class/hwmon/hwmon*/name | head -1))/power1_cap\n\n  # negative write\n  echo -1000000 \u003e $CAP ; echo \"ret=$?\"\n  # valid positive write must still work\n  echo 400000000 \u003e $CAP ; echo \"ret=$?\"\n\nBefore:\n  # echo -1000000 \u003e $CAP ; echo \"ret=$?\"\n  ret=0                             \u003c- accepted; bogus limit sent to SMU\n  # echo 400000000 \u003e $CAP ; echo \"ret=$?\"\n  ret=0\n\nAfter:\n  # echo -1000000 \u003e $CAP ; echo \"ret=$?\"\n  bash: echo: write error: Invalid argument\n  ret=1                             \u003c- rejected with -EINVAL\n  # echo 400000000 \u003e $CAP ; echo \"ret=$?\"\n  ret=0                             \u003c- valid write still works","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":"platform/x86/amd/hsmp: Reject negative power cap writes in hwmon","id":"CVE-2026-90136","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"integer_overflow","year":"2026"},"n_packages":0,"n_references":3,"next":{"headline":"platform/x86: hp-bioscfg: fix password encoding bounds check","id":"CVE-2026-90137"},"packages":[],"prev":{"headline":"net: add missing ref_tracker_dir_exit() to alloc_netdev_mqs()","id":"CVE-2026-90135"},"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 local attacker with root privileges can write negative values to the AMD HSMP power cap, causing an integer overflow that sends invalid multi-gigawatt limits to the SMU.","url":"https://insights.sbomify.com/CVE-2026-90136/"}