{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2024-46754", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-09-11T15:12:18.270Z", "datePublished": "2024-09-18T07:12:13.780Z", "dateUpdated": "2026-08-05T11:38:22.407Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:38:22.407Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Remove tst_run from lwt_seg6local_prog_ops.\n\nThe syzbot reported that the lwt_seg6 related BPF ops can be invoked\nvia bpf_test_run() without without entering input_action_end_bpf()\nfirst.\n\nMartin KaFai Lau said that self test for BPF_PROG_TYPE_LWT_SEG6LOCAL\nprobably didn't work since it was introduced in commit 04d4b274e2a\n(\"ipv6: sr: Add seg6local action End.BPF\"). The reason is that the\nper-CPU variable seg6_bpf_srh_states::srh is never assigned in the self\ntest case but each BPF function expects it.\n\nRemove test_run for BPF_PROG_TYPE_LWT_SEG6LOCAL." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The only entry point is the local `bpf(BPF_PROG_TEST_RUN)` syscall against a `BPF_PROG_TYPE_LWT_SEG6LOCAL` program fd; no packet ever reaches this path from the network, since real SRv6 traffic goes through `input_action_end_bpf()` which initializes the state correctly.\nAC:L - A single `BPF_PROG_TEST_RUN` calling `bpf_lwt_seg6_action(END_B6_ENCAP)` deterministically hits `dev_net(skb_dst(skb)->dev)` with a NULL dst, with no race, no timing window and no layout luck; the UAF variant needs only ordinary heap grooming that the attacker fully drives by choosing `data_size_in` (slab cache), `srhoff` (offset) and CPU affinity.\nPR:L - `bpf_prog_test_run()` itself performs zero capability check — it only does `bpf_prog_get(attr->test.prog_fd)` — so any unprivileged local process that inherits or receives a seg6local program fd (fork/exec, `SCM_RIGHTS`, or a permissively-moded bpffs pin) can trigger it, and BPF tokens in 6.9+ deliberately delegate `CAP_BPF`/`CAP_NET_ADMIN` program loading to unprivileged users inside containers.\nUI:N - The attacker issues the `bpf()` syscalls entirely on their own; no victim action, mount, file open, or administrator step is involved at any point.\nS:U - The NULL dereference, out-of-bounds read and slab use-after-free all occur in kernel context within the same security authority the calling process already interacts with; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - The dangling per-CPU `srh_state->srh` lets `seg6_validate_srh()` walk TLVs through a freed, attacker-reclaimed slab object, and `seg6_do_srh_inline()`'s `memmove(hdr, oldhdr, 40)` on a short test packet reads up to 40 bytes past `skb->tail` which are then returned to userspace via `bpf_test_finish()`'s `data_out`.\nI:H - `seg6_bpf_has_valid_srh()` executes `srh->hdrlen = (u8)(srh_state->hdrlen >> 3)` through the stale pointer, giving an attacker-valued one-byte write at an attacker-chosen offset inside a freed object in an attacker-selected kmalloc cache — a reclaim primitive suitable for corrupting length/flag fields of a sprayed victim structure and escalating.\nA:H - `bpf_lwt_seg6_action(END_B6_ENCAP)` reliably oopses the kernel on `dev_net(skb_dst(skb)->dev)` because the test skb carries no dst, and post-`d1542d4ae4df` the same path also trips `lockdep_assert_held()`, which is a panic under `panic_on_warn`." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/core/filter.c" ], "versions": [ { "version": "004d4b274e2a1a895a0e5dc66158b90a7d463d44", "lessThan": "9cd15511de7c619bbd0f54bb3f28e6e720ded5d6", "status": "affected", "versionType": "git" }, { "version": "004d4b274e2a1a895a0e5dc66158b90a7d463d44", "lessThan": "c13fda93aca118b8e5cd202e339046728ee7dddb", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/core/filter.c" ], "versions": [ { "version": "4.18", "status": "affected" }, { "version": "0", "lessThan": "4.18", "status": "unaffected", "versionType": "semver" }, { "version": "6.10.10", "lessThanOrEqual": "6.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.11", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.18", "versionEndExcluding": "6.10.10" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.18", "versionEndExcluding": "6.11" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/9cd15511de7c619bbd0f54bb3f28e6e720ded5d6" }, { "url": "https://git.kernel.org/stable/c/c13fda93aca118b8e5cd202e339046728ee7dddb" } ], "title": "bpf: Remove tst_run from lwt_seg6local_prog_ops.", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "timestamp": "2024-09-29T14:46:48.262114Z", "id": "CVE-2024-46754", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "role": "CISA Coordinator", "version": "2.0.3" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-09-29T14:47:03.068Z" } } ] } }