{"answers":{"affected":"It affects 1 product.","exploited":"There is no known exploitation of CVE-2026-23438 in the wild and no public exploit code.","fix":"Apply the vendor's patch.","what":"CVE-2026-23438 is a medium-severity vulnerability in Linux kernel, published on 3 Apr 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-2026-23438 and fix it if it is affected.\n\nWhat it is: CVE-2026-23438 is a medium-severity vulnerability in Linux kernel, published on 3 Apr 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-2026-23438 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-2026-23438/ (Markdown: https://insights.sbomify.com/CVE-2026-23438/index.md)","id":"CVE-2026-23438","markdown":"https://insights.sbomify.com/CVE-2026-23438/index.md","name":"CVE-2026-23438","record":{"aliases":["BELL-CVE-2026-23438","DEBIAN-CVE-2026-23438","GHSA-4m78-cvj8-m5m2","ROOT-OS-DEBIAN-12-CVE-2026-23438","ROOT-OS-DEBIAN-13-CVE-2026-23438","ROOT-OS-UBUNTU-2204-CVE-2026-23438","ROOT-OS-UBUNTU-2404-CVE-2026-23438","UBUNTU-CVE-2026-23438"],"analysis":{"component_type":"kernel","fix_type":"patch","impacts":["denial_of_service"],"network_reachable":"adjacent_or_local","non_default_config":true,"product_category":"Linux kernel network driver","requires_auth":"low_privilege","summary":"A missing NULL check in the Marvell mvpp2 network driver causes a kernel crash when changing MTU on systems without CM3 SRAM, leading to denial of service.","user_interaction":"not_required","vuln_class":"null_dereference"},"analysis_generated_by":"qwen3.8-flash-next","assigner":"Linux","cpe":[{"product":"linux_kernel","vendor":"linux"}],"cvss":{"score":5.5,"severity":"medium","source":"nvd","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},"cwes":[{"id":"CWE-476","name":"NULL Pointer Dereference"}],"description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: mvpp2: guard flow control update with global_tx_fc in buffer switching\n\nmvpp2_bm_switch_buffers() unconditionally calls\nmvpp2_bm_pool_update_priv_fc() when switching between per-cpu and\nshared buffer pool modes. This function programs CM3 flow control\nregisters via mvpp2_cm3_read()/mvpp2_cm3_write(), which dereference\npriv-\u003ecm3_base without any NULL check.\n\nWhen the CM3 SRAM resource is not present in the device tree (the\nthird reg entry added by commit 60523583b07c (\"dts: marvell: add CM3\nSRAM memory to cp11x ethernet device tree\")), priv-\u003ecm3_base remains\nNULL and priv-\u003eglobal_tx_fc is false. Any operation that triggers\nmvpp2_bm_switch_buffers(), for example an MTU change that crosses\nthe jumbo frame threshold, will crash:\n\n  Unable to handle kernel NULL pointer dereference at\n  virtual address 0000000000000000\n  Mem abort info:\n    ESR = 0x0000000096000006\n    EC = 0x25: DABT (current EL), IL = 32 bits\n  pc : readl+0x0/0x18\n  lr : mvpp2_cm3_read.isra.0+0x14/0x20\n  Call trace:\n   readl+0x0/0x18\n   mvpp2_bm_pool_update_fc+0x40/0x12c\n   mvpp2_bm_pool_update_priv_fc+0x94/0xd8\n   mvpp2_bm_switch_buffers.isra.0+0x80/0x1c0\n   mvpp2_change_mtu+0x140/0x380\n   __dev_set_mtu+0x1c/0x38\n   dev_set_mtu_ext+0x78/0x118\n   dev_set_mtu+0x48/0xa8\n   dev_ifsioc+0x21c/0x43c\n   dev_ioctl+0x2d8/0x42c\n   sock_ioctl+0x314/0x378\n\nEvery other flow control call site in the driver already guards\nhardware access with either priv-\u003eglobal_tx_fc or port-\u003etx_fc.\nmvpp2_bm_switch_buffers() is the only place that omits this check.\n\nAdd the missing priv-\u003eglobal_tx_fc guard to both the disable and\nre-enable calls in mvpp2_bm_switch_buffers(), consistent with the\nrest of the driver.","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":"net: mvpp2: guard flow control update with global_tx_fc in buffer switching","id":"CVE-2026-23438","indexable":true,"kev":null,"kind":"cve","links":{"ecosystem":null,"product":"linux:linux_kernel","products":["linux:linux_kernel"],"type":"null_dereference","year":"2026"},"n_packages":0,"n_references":7,"next":{"headline":"udp_tunnel: fix NULL deref caused by udp_sock_create6 when CONFIG_IPV6=n","id":"CVE-2026-23439"},"packages":[],"prev":{"headline":"net: shaper: protect late read accesses to the hierarchy","id":"CVE-2026-23437"},"products":["Linux"],"published":"2026-04-03","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":null,"exploitation":null,"technical_impact":null},"state":"PUBLISHED","updated":"2026-10-15","vendors":["Linux"]},"summary":"A missing NULL check in the Marvell mvpp2 network driver causes a kernel crash when changing MTU on systems without CM3 SRAM, leading to denial of service.","url":"https://insights.sbomify.com/CVE-2026-23438/"}