{"answers":{"affected":"","exploited":"There is no known exploitation of CVE-2026-68124 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-68124 is a critical memory corruption vulnerability in Linux, published on 10 Aug 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-2026-68124 and fix it if it is affected.\n\nWhat it is: CVE-2026-68124 is a critical memory corruption vulnerability in Linux, published on 10 Aug 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-2026-68124 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-2026-68124/ (Markdown: https://insights.sbomify.com/CVE-2026-68124/index.md)","id":"CVE-2026-68124","markdown":"https://insights.sbomify.com/CVE-2026-68124/index.md","name":"CVE-2026-68124","record":{"aliases":["BELL-CVE-2026-68124","DEBIAN-CVE-2026-68124","GHSA-c8wc-v527-8f9g","UBUNTU-CVE-2026-68124"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["code_execution","privilege_escalation"],"network_reachable":"adjacent_or_local","non_default_config":true,"product_category":"Linux kernel MCTP","requires_auth":"none","summary":"A zero-length frame in the Linux kernel MCTP serial driver causes an out-of-bounds heap write, potentially allowing code execution or privilege escalation.","user_interaction":"not_required","vuln_class":"memory_corruption"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[],"cvss":{"score":9.6,"severity":"critical","source":"cna","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","version":"3.1"},"cwes":[],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nmctp: serial: handle zero-length frames to prevent rx buffer overflow\n\nThe MCTP serial receive state machine reads a frame length byte in\nmctp_serial_push_header() case 2 and validates it upper-bound-only:\n\n\tif (c \u003e MCTP_SERIAL_FRAME_MTU) {\n\t\tdev-\u003erxstate = STATE_ERR;\n\t} else {\n\t\tdev-\u003erxlen = c;\n\t\tdev-\u003erxpos = 0;\n\t\tdev-\u003erxstate = STATE_DATA;\n\t\t...\n\t}\n\nA length of zero passes this check, so rxlen is set to 0 and the state\nmachine advances to STATE_DATA. In mctp_serial_push() STATE_DATA, the\nincoming byte is stored and rxpos incremented before the terminator is\n\n\tdev-\u003erxbuf[dev-\u003erxpos] = c;\n\tdev-\u003erxpos++;\n\tdev-\u003erxstate = STATE_DATA;\n\tif (dev-\u003erxpos == dev-\u003erxlen) {\n\t\tdev-\u003erxpos = 0;\n\t\tdev-\u003erxstate = STATE_TRAILER;\n\t}\n\nWith rxlen == 0 the \"rxpos == rxlen\" terminator can never fire (rxpos is\nalready 1 on the first data byte), so subsequent bytes are written past\nthe end of the fixed 74-byte rxbuf, which is the last member of the\nnetdev private area. Every following data byte is an attacker-controlled\n1-byte out-of-bounds heap write, and the overflow continues until a\nframe (0x7e) or escape byte resets the parser -- effectively unbounded.\n\nReaching this requires CAP_NET_ADMIN to attach the N_MCTP line\ndiscipline and bring the resulting mctpserialN netdev up, after which\nthe bytes arrive via the tty receive path.\n\nRoute a zero-length frame straight to STATE_TRAILER instead of\nSTATE_DATA. The trailer/framing bytes are still consumed, and the frame\nresolves to a zero-length skb that the MCTP core rejects; the parser\nnever enters STATE_DATA with rxlen == 0, so the out-of-bounds write can\nno longer occur.\n\nKASAN, on a frame of 0x7e 0x01 0x00 followed by data bytes (before this\nchange):\n\n  UBSAN: array-index-out-of-bounds in drivers/net/mctp/mctp-serial.c:370\n  index 74 is out of range for type 'u8 [74]'\n  BUG: KASAN: slab-out-of-bounds in mctp_serial_tty_receive_buf\n  Write of size 1 at addr ... by task kworker/u16:0\n   mctp_serial_tty_receive_buf\n   tty_ldisc_receive_buf\n   flush_to_ldisc\n  Allocated by task 152:\n   alloc_netdev_mqs\n   mctp_serial_open\n\nv2: route zero-length frames to STATE_TRAILER instead of STATE_ERR so\n    the trailer/framing bytes are still consumed (Jeremy Kerr).\n\nFound by 0sec automated security-research tooling (https://0sec.ai).","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":"mctp: serial: handle zero-length frames to prevent rx buffer overflow","id":"CVE-2026-68124","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":null,"products":[],"type":"memory_corruption","year":"2026"},"n_packages":0,"n_references":6,"next":{"headline":"mac802154: llsec: reject frames shorter than the authentication tag","id":"CVE-2026-68125"},"packages":[],"prev":{"headline":"openvswitch: fix GSO userspace truncation underflow","id":"CVE-2026-68123"},"products":["Linux"],"published":"2026-08-10","related":[],"sources":[{"class":"attribution","licence":"CVE Terms of Use (MITRE)","name":"CVE List","prefix":"CVE"},{"class":"attribution","licence":"FIRST CVSS licence","name":"CVSS (FIRST)"}],"ssvc":{"automatable":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-08-19","vendors":["Linux"]},"summary":"A zero-length frame in the Linux kernel MCTP serial driver causes an out-of-bounds heap write, potentially allowing code execution or privilege escalation.","url":"https://insights.sbomify.com/CVE-2026-68124/"}