{ "schema_version": "1.6.1", "id": "RPI-CVE-2024-26851", "modified": "2026-10-09T11:39:44Z", "upstream": [ "CVE-2024-26851" ], "published": "2024-04-17T10:17:34Z", "summary": "netfilter: nf_conntrack_h323: Add protection for bmp length out of range", "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_conntrack_h323: Add protection for bmp length out of range\n\nUBSAN load reports an exception of BRK#5515 SHIFT_ISSUE:Bitwise shifts\nthat are out of bounds for their data type.\n\nvmlinux get_bitmap(b=75) + 712\n\nvmlinux decode_seq(bs=0xFFFFFFD008037000, f=0xFFFFFFD008037018, level=134443100) + 1956\n\nvmlinux decode_choice(base=0xFFFFFFD0080370F0, level=23843636) + 1216\n\nvmlinux decode_seq(f=0xFFFFFFD0080371A8, level=134443500) + 812\n\nvmlinux decode_choice(base=0xFFFFFFD008037280, level=0) + 1216\n\nvmlinux DecodeRasMessage() + 304\n\nvmlinux ras_help() + 684\n\nvmlinux nf_confirm() + 188\n\n\nDue to abnormal data in skb->data, the extension bitmap length\nexceeds 32 when decoding ras message then uses the length to make\na shift operation. It will change into negative after several loop.\nUBSAN load could detect a negative shift as an undefined behaviour\nand reports exception.\nSo we add the protection to avoid the length exceeding 32. Or else\nit will return out of range error and stop decoding.", "severity": [ { "type": "CVSS_V3", "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H" } ], "affected": [ { "package": { "ecosystem": "Raspberry Pi OS:12", "name": "linux" }, "versions": [ "1:6.1.21-1+rpt1", "1:6.1.47-1+rpt2", "1:6.1.47-1+rpt4", "1:6.1.54-1+rpt2", "1:6.1.58-1+rpt2", "1:6.1.63-1+rpt1", "1:6.1.73-1+rpt1", "1:6.6.20-1+rpt1" ], "ecosystem_specific": { "binaries": [ { "binary_name": "linux-image-6.1.0-rpi1-rpi-v6", "binary_version": "1:6.1.21-1+rpt1" }, { "binary_name": "linux-image-6.1.0-rpi1-rpi-v7", "binary_version": "1:6.1.21-1+rpt1" }, { "binary_name": "linux-image-6.1.0-rpi1-rpi-v7l", "binary_version": "1:6.1.21-1+rpt1" }, { "binary_name": "linux-image-6.1.0-rpi1-rpi-v8", "binary_version": "1:6.1.21-1+rpt1" }, { "binary_name": "linux-image-6.1.0-rpi2-rpi-v6", "binary_version": "1:6.1.47-1+rpt2" }, { "binary_name": "linux-image-6.1.0-rpi2-rpi-v7", "binary_version": "1:6.1.47-1+rpt2" }, { "binary_name": "linux-image-6.1.0-rpi2-rpi-v7l", "binary_version": "1:6.1.47-1+rpt2" }, { "binary_name": "linux-image-6.1.0-rpi2-rpi-v8", "binary_version": "1:6.1.47-1+rpt2" }, { "binary_name": "linux-image-6.1.0-rpi3-rpi-2712", "binary_version": "1:6.1.47-1+rpt4" }, { "binary_name": "linux-image-6.1.0-rpi3-rpi-v6", "binary_version": "1:6.1.47-1+rpt4" }, { "binary_name": "linux-image-6.1.0-rpi3-rpi-v7", "binary_version": "1:6.1.47-1+rpt4" }, { "binary_name": "linux-image-6.1.0-rpi3-rpi-v7l", "binary_version": "1:6.1.47-1+rpt4" }, { "binary_name": "linux-image-6.1.0-rpi3-rpi-v8", "binary_version": "1:6.1.47-1+rpt4" }, { "binary_name": "linux-image-6.1.0-rpi4-rpi-2712", "binary_version": "1:6.1.54-1+rpt2" }, { "binary_name": "linux-image-6.1.0-rpi4-rpi-v6", "binary_version": "1:6.1.54-1+rpt2" }, { "binary_name": "linux-image-6.1.0-rpi4-rpi-v7", "binary_version": "1:6.1.54-1+rpt2" }, { "binary_name": "linux-image-6.1.0-rpi4-rpi-v7l", "binary_version": "1:6.1.54-1+rpt2" }, { "binary_name": "linux-image-6.1.0-rpi4-rpi-v8", "binary_version": "1:6.1.54-1+rpt2" }, { "binary_name": "linux-image-6.1.0-rpi6-rpi-2712", "binary_version": "1:6.1.58-1+rpt2" }, { "binary_name": "linux-image-6.1.0-rpi6-rpi-v6", "binary_version": "1:6.1.58-1+rpt2" }, { "binary_name": "linux-image-6.1.0-rpi6-rpi-v7", "binary_version": "1:6.1.58-1+rpt2" }, { "binary_name": "linux-image-6.1.0-rpi6-rpi-v7l", "binary_version": "1:6.1.58-1+rpt2" }, { "binary_name": "linux-image-6.1.0-rpi6-rpi-v8", "binary_version": "1:6.1.58-1+rpt2" }, { "binary_name": "linux-image-6.1.0-rpi7-rpi-2712", "binary_version": "1:6.1.63-1+rpt1" }, { "binary_name": "linux-image-6.1.0-rpi7-rpi-v6", "binary_version": "1:6.1.63-1+rpt1" }, { "binary_name": "linux-image-6.1.0-rpi7-rpi-v7", "binary_version": "1:6.1.63-1+rpt1" }, { "binary_name": "linux-image-6.1.0-rpi7-rpi-v7l", "binary_version": "1:6.1.63-1+rpt1" }, { "binary_name": "linux-image-6.1.0-rpi7-rpi-v8", "binary_version": "1:6.1.63-1+rpt1" }, { "binary_name": "linux-image-6.1.0-rpi8-rpi-2712", "binary_version": "1:6.1.73-1+rpt1" }, { "binary_name": "linux-image-6.1.0-rpi8-rpi-v6", "binary_version": "1:6.1.73-1+rpt1" }, { "binary_name": "linux-image-6.1.0-rpi8-rpi-v7", "binary_version": "1:6.1.73-1+rpt1" }, { "binary_name": "linux-image-6.1.0-rpi8-rpi-v7l", "binary_version": "1:6.1.73-1+rpt1" }, { "binary_name": "linux-image-6.1.0-rpi8-rpi-v8", "binary_version": "1:6.1.73-1+rpt1" }, { "binary_name": "linux-image-6.6.20+rpt-rpi-2712", "binary_version": "1:6.6.20-1+rpt1" }, { "binary_name": "linux-image-6.6.20+rpt-rpi-v6", "binary_version": "1:6.6.20-1+rpt1" }, { "binary_name": "linux-image-6.6.20+rpt-rpi-v7", "binary_version": "1:6.6.20-1+rpt1" }, { "binary_name": "linux-image-6.6.20+rpt-rpi-v7l", "binary_version": "1:6.6.20-1+rpt1" }, { "binary_name": "linux-image-6.6.20+rpt-rpi-v8", "binary_version": "1:6.6.20-1+rpt1" } ] }, "database_specific": { "per_version": { "1:6.1.21-1+rpt1": { "linux_commit": "0afb5e98488aed7017b9bf321b575d0177feb7ed", "upstream_version": "6.1.21", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.1.82" }, "1:6.1.47-1+rpt2": { "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e", "upstream_version": "6.1.47", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.1.82" }, "1:6.1.47-1+rpt4": { "linux_commit": "655fc658a15ae7a6f37103754adb39ba52a9a14e", "upstream_version": "6.1.47", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.1.82", "compiled_filter": false }, "1:6.1.54-1+rpt2": { "linux_commit": "2906f7abdc03d4a92b6b0e2e0c87ea2a9dffe8f7", "upstream_version": "6.1.54", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.1.82" }, "1:6.1.58-1+rpt2": { "linux_commit": "ccf1586ad0663fa91238ac56abf6340d6d740d18", "upstream_version": "6.1.58", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.1.82" }, "1:6.1.63-1+rpt1": { "linux_commit": null, "upstream_version": "6.1.63", "assessment": "upstream version (no usable Linux commit)", "upstream_fixed": "6.1.82" }, "1:6.1.73-1+rpt1": { "linux_commit": null, "upstream_version": "6.1.73", "assessment": "upstream version (no usable Linux commit)", "upstream_fixed": "6.1.82" }, "1:6.6.20-1+rpt1": { "linux_commit": "6f16847710cc0502450788b9f12f0a14d3429668", "upstream_version": "6.6.20", "assessment": "commit ancestry (strak rule)", "upstream_fixed": "6.6.22" } } } } ], "references": [ { "type": "ADVISORY", "url": "https://www.cve.org/CVERecord?id=CVE-2024-26851" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/98db42191329c679f4ca52bec0b319689e1ad8cb" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/4bafcc43baf7bcf93566394dbd15726b5b456b7a" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/ccd1108b16ab572d9bf635586b0925635dbd6bbc" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/b3c0f553820516ad4b62a9390ecd28d6f73a7b13" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/39001e3c42000e7c2038717af0d33c32319ad591" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/014a807f1cc9c9d5173c1cd935835553b00d211c" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/80ee5054435a11c87c9a4f30f1ff750080c96416" }, { "type": "FIX", "url": "https://git.kernel.org/stable/c/767146637efc528b5e3d31297df115e85a2fd362" } ], "database_specific": { "source": "https://git.kernel.org/pub/scm/linux/security/vulns.git", "upstream_modified": "2026-08-05T11:52:36Z", "severity": { "source": "kernel CNA", "cvss_v3_score": 7.5, "cvss_v3_severity": "High", "scenario": "AV:N - The vulnerable decoder is driven entirely by attacker-supplied packet payload \u2014 a UDP datagram to port 1719 (RAS) or TCP 1720 (Q.931) processed by the in-kernel H.323 conntrack helper on any Linux router, firewall, or CPE with the ALG active. The attacker can be anywhere on the internet.\nAC:L - The 7-bit extension-bitmap length field is read verbatim from the packet, so the attacker simply sets it above 32 to force the out-of-range shift \u2014 deterministic, single packet, no timing or memory-layout dependency.\nPR:N - The helper runs on the very first packet of the flow (the trace shows it invoked from nf_confirm()), before any application-level state, credentials, or connection setup exist. A completely unauthenticated remote host triggers it.\nUI:N - Packet processing happens in softirq context on the conntrack hook with no involvement from any local user or administrator.\nS:U - The undefined behavior and its consequences are confined to the kernel of the host running the conntrack helper; no VM, IOMMU, or sandbox boundary is crossed.\nC:N - The out-of-range shift produces a garbage value in a local bitmap variable; the byte reads are still covered by nf_h323_error_boundary() and nothing is returned to the attacker, so there is no read primitive or information disclosure.\nI:N - There is no out-of-bounds write and no corruption of adjacent state \u2014 the extension loop remains bounded by f->ub, so the effect is a misparse of the attacker's own message rather than modification of kernel data.\nA:H - On kernels built with the UBSAN shift sanitizer in trap mode (widely deployed on Android/vendor kernels, and the exact configuration in the bug report) the out-of-range shift raises a BRK exception and panics the kernel, so one unauthenticated remote packet takes the box down." } } }