CVE-2024-26851

netfilter: nf_conntrack_h323: Add protection for bmp length out of range

Published Apr 17, 2024 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Description
In the Linux kernel, the following vulnerability has been resolved:

netfilter: nf_conntrack_h323: Add protection for bmp length out of range

UBSAN load reports an exception of BRK#5515 SHIFT_ISSUE:Bitwise shifts
that are out of bounds for their data type.

vmlinux get_bitmap(b=75) + 712
<net/netfilter/nf_conntrack_h323_asn1.c:0>
vmlinux decode_seq(bs=0xFFFFFFD008037000, f=0xFFFFFFD008037018, level=134443100) + 1956
<net/netfilter/nf_conntrack_h323_asn1.c:592>
vmlinux decode_choice(base=0xFFFFFFD0080370F0, level=23843636) + 1216
<net/netfilter/nf_conntrack_h323_asn1.c:814>
vmlinux decode_seq(f=0xFFFFFFD0080371A8, level=134443500) + 812
<net/netfilter/nf_conntrack_h323_asn1.c:576>
vmlinux decode_choice(base=0xFFFFFFD008037280, level=0) + 1216
<net/netfilter/nf_conntrack_h323_asn1.c:814>
vmlinux DecodeRasMessage() + 304
<net/netfilter/nf_conntrack_h323_asn1.c:833>
vmlinux ras_help() + 684
<net/netfilter/nf_conntrack_h323_main.c:1728>
vmlinux nf_confirm() + 188
<net/netfilter/nf_conntrack_proto.c:137>

Due to abnormal data in skb->data, the extension bitmap length
exceeds 32 when decoding ras message then uses the length to make
a shift operation. It will change into negative after several loop.
UBSAN load could detect a negative shift as an undefined behaviour
and reports exception.
So we add the protection to avoid the length exceeding 32. Or else
it will return out of range error and stop decoding.

Analysis

No analysis available yet

Remediation

No remediation available yet

Tracking

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Advisories

Source ID Title
Debian DLA Debian DLA DLA-3840-1 linux security update
Debian DLA Debian DLA DLA-3842-1 linux-5.10 security update
Debian DSA Debian DSA DSA-5681-1 linux security update
Ubuntu USN Ubuntu USN USN-6820-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6820-2 Linux kernel (NVIDIA) vulnerabilities
Ubuntu USN Ubuntu USN USN-6821-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6821-2 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6821-3 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-6821-4 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-6828-1 Linux kernel (Intel IoTG) vulnerabilities
Ubuntu USN Ubuntu USN USN-6871-1 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-6892-1 Linux kernel (IBM) vulnerabilities
Ubuntu USN Ubuntu USN USN-6896-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6896-2 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6896-3 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6896-4 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6896-5 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6919-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7028-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-7028-2 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-7039-1 Linux kernel vulnerabilities
History
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Type Values Removed Values Added
First Time appeared Debian
Debian debian Linux
Linux
Linux linux Kernel
Weaknesses CWE-787
CPEs cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.8:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.8:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.8:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.8:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.8:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.8:rc6:*:*:*:*:*:*
Vendors & Products Debian
Debian debian Linux
Linux
Linux linux Kernel
Type Values Removed Values Added
CPEs cpe:/a:redhat:rhel_eus:9.4
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Redhat enterprise Linux
CPEs cpe:/a:redhat:enterprise_linux:8::nfv
cpe:/o:redhat:enterprise_linux:8
Vendors & Products Redhat enterprise Linux
Type Values Removed Values Added
First Time appeared Redhat
Redhat rhel Eus
CPEs cpe:/o:redhat:rhel_eus:8.8
Vendors & Products Redhat
Redhat rhel Eus
Weaknesses

Sources

Status
PUBLISHED
Assigner
Linux
Published
Updated
Oct 15, 2026, 12:38 AM
Reserved
Feb 19, 2024, 2:20 PM
Status
Modified
Published
Apr 17, 2024, 11:15 AM
Modified
Oct 15, 2026, 1:17 AM
Severity
Moderate
Public date
Apr 17, 2024, 12:00 AM