Linux Kernel: Out-of-Bounds Access (CVE-2024-26851)
Published Last modified Sources: Siemens ProductCERT, Debian, SUSE, Red Hat, CVE.org, EUVD, BSI
What is affected, what to do
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.
Update Linux Kernel to version 4.19.310, Linux Kernel to version 5.4.272, Linux Kernel to version 5.10.213.
- Affected
- Linux Kernel
lt 2.6.17..4.19.310 - Linux Kernel
lt 4.20..5.4.272 - Linux Kernel
lt 5.5..5.10.213 - Linux Kernel
lt 5.11..5.15.152 - Linux Kernel
lt 5.16..6.1.82 - Linux Kernel
lt 6.2..6.6.22 - Linux Kernel
lt 6.7..6.7.10
- Linux Kernel
- Fixed in
- Linux Kernel
4.19.310 - Linux Kernel
5.4.272 - Linux Kernel
5.10.213 - Linux Kernel
5.15.152 - Linux Kernel
6.1.82 - Linux Kernel
6.6.22 - Linux Kernel
6.7.10 - Linux Kernel
6.8
- Linux Kernel
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Metrics
7.5
XIEM Effective CVSS
Highest available CVSS rating from NVD and vendor data.
Source: Vendor (CNA), CVSS v3
7.5
CVSS v3
Severity High on the scale from 0 to 10.
Source: Siemens ProductCERT, Debian, SUSE, Red Hat, CVE.org, EUVD, BSI
0.7 %
EPSS score
Low — model estimates < 1% exploitation likelihood.
Source: FIRST EPSS, percentile 55.2
Show all metrics
- Severity
- High
Priority (0–325)
The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?
Read in glossary- 66.72 Methodology
Exploit maturity
An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.
Read in glossary- no public PoC known
XIEM Effective CVSS
XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.
Read in glossary- 7.5 Methodology
CVSS v3
CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.
Read in glossary- 7.5
EPSS score
The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.
Read in glossary- 0.7 %
- Low — model estimates < 1% exploitation likelihood.
EPSS percentile
The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.
Read in glossary- 55.2
- High — this CVE ranks above the median of all CVEs scored today (rank ≥ 36%).
KEV status
The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.
Read in glossary- —
- Published
- CISA assessment (SSVC)
- Exploitation: none known · not automatable · Technical impact: total
- Source: CISA Vulnrichment, as of 12 June 2024
Detection rules
No NEOSEC detection rule is available for this vulnerability yet.
Classification under NIS2 and CRA
Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.
NIS2
NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.
Read in glossary- High technical severity: assess and remediate the vulnerability in vulnerability handling under Art. 21(2)(e) NIS2 and document the decision.
CRA
The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.
Read in glossary- From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
ISO/IEC 27001
ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.
Read in glossary- Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.
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.
Source: siemens_advisory, Debian Security Advisories, suse_csaf, redhat_csaf, cvelistv5, NVD (NIST), ENISA EUVD, BSI CSAF, BSI WID Portal
Affected products
The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.
| Affected versions | Fixed in | ||
|---|---|---|---|
| Linux | Linux |
|
|
Vendors and products
Affected operating systems
| Linux | debian | debian_linux | 10.0 |
| Linux | debian | linux | bullseye |
| Linux | linux | linux_kernel | 6.8 |
| Linux | linux | linux_kernel | — |
References & sources
- git.kernel.orgstable/c/98db42191329c679f4ca52bec0b319689e1ad8cbeuvd
- git.kernel.orgstable/c/4bafcc43baf7bcf93566394dbd15726b5b456b7aeuvd
- git.kernel.orgstable/c/ccd1108b16ab572d9bf635586b0925635dbd6bbceuvd
- git.kernel.orgstable/c/b3c0f553820516ad4b62a9390ecd28d6f73a7b13euvd
- git.kernel.orgstable/c/39001e3c42000e7c2038717af0d33c32319ad591euvd
- git.kernel.orgstable/c/014a807f1cc9c9d5173c1cd935835553b00d211ceuvd
- git.kernel.orgstable/c/80ee5054435a11c87c9a4f30f1ff750080c96416euvd
- git.kernel.orgstable/c/767146637efc528b5e3d31297df115e85a2fd362euvd
- lists.debian.orgdebian-lts-announce/2024/06/msg00017.htmlx_transferred
- lists.debian.orgdebian-lts-announce/2024/06/msg00020.htmlx_transferred
- Siemens ProductCERTproductcert/html/ssa-265688.html
Changes to this CVE
Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).
Record modifiedLinux
New references:- https://git.kernel.org/stable/c/014a807f1cc9c9d5173c1cd935835553b00d211c
- https://git.kernel.org/stable/c/39001e3c42000e7c2038717af0d33c32319ad591
- https://git.kernel.org/stable/c/4bafcc43baf7bcf93566394dbd15726b5b456b7a
- https://git.kernel.org/stable/c/767146637efc528b5e3d31297df115e85a2fd362
and 4 more references
Show 24 original changes
Individual changes of this event as published by NVD Type Action Before After Reference added —https://git.kernel.org/stable/c/014a807f1cc9c9d5173c1cd935835553b00d211cReference added —https://git.kernel.org/stable/c/39001e3c42000e7c2038717af0d33c32319ad591Reference added —https://git.kernel.org/stable/c/4bafcc43baf7bcf93566394dbd15726b5b456b7aReference added —https://git.kernel.org/stable/c/767146637efc528b5e3d31297df115e85a2fd362Reference added —https://git.kernel.org/stable/c/80ee5054435a11c87c9a4f30f1ff750080c96416Reference added —https://git.kernel.org/stable/c/98db42191329c679f4ca52bec0b319689e1ad8cbReference added —https://git.kernel.org/stable/c/b3c0f553820516ad4b62a9390ecd28d6f73a7b13Reference added —https://git.kernel.org/stable/c/ccd1108b16ab572d9bf635586b0925635dbd6bbcReference removed https://git.kernel.org/stable/c/014a807f1cc9c9d5173c1cd935835553b00d211c—Reference removed https://git.kernel.org/stable/c/39001e3c42000e7c2038717af0d33c32319ad591—Reference removed https://git.kernel.org/stable/c/4bafcc43baf7bcf93566394dbd15726b5b456b7a—Reference removed https://git.kernel.org/stable/c/767146637efc528b5e3d31297df115e85a2fd362—Reference removed https://git.kernel.org/stable/c/80ee5054435a11c87c9a4f30f1ff750080c96416—Reference removed https://git.kernel.org/stable/c/98db42191329c679f4ca52bec0b319689e1ad8cb—Reference removed https://git.kernel.org/stable/c/b3c0f553820516ad4b62a9390ecd28d6f73a7b13—Reference removed https://git.kernel.org/stable/c/ccd1108b16ab572d9bf635586b0925635dbd6bbc—Reference type removed https://git.kernel.org/stable/c/014a807f1cc9c9d5173c1cd935835553b00d211c Types: Patch—Reference type removed https://git.kernel.org/stable/c/39001e3c42000e7c2038717af0d33c32319ad591 Types: Patch—Reference type removed https://git.kernel.org/stable/c/4bafcc43baf7bcf93566394dbd15726b5b456b7a Types: Patch—Reference type removed https://git.kernel.org/stable/c/767146637efc528b5e3d31297df115e85a2fd362 Types: Patch—Reference type removed https://git.kernel.org/stable/c/80ee5054435a11c87c9a4f30f1ff750080c96416 Types: Patch—Reference type removed https://git.kernel.org/stable/c/98db42191329c679f4ca52bec0b319689e1ad8cb Types: Patch—Reference type removed https://git.kernel.org/stable/c/b3c0f553820516ad4b62a9390ecd28d6f73a7b13 Types: Patch—Reference type removed https://git.kernel.org/stable/c/ccd1108b16ab572d9bf635586b0925635dbd6bbc Types: Patch—Source identifier: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Record modifiedCVE Program
New references:- https://git.kernel.org/stable/c/014a807f1cc9c9d5173c1cd935835553b00d211c
- https://git.kernel.org/stable/c/39001e3c42000e7c2038717af0d33c32319ad591
- https://git.kernel.org/stable/c/4bafcc43baf7bcf93566394dbd15726b5b456b7a
- https://git.kernel.org/stable/c/767146637efc528b5e3d31297df115e85a2fd362
and 6 more references
Show 30 original changes
Individual changes of this event as published by NVD Type Action Before After Reference added —https://git.kernel.org/stable/c/014a807f1cc9c9d5173c1cd935835553b00d211cReference added —https://git.kernel.org/stable/c/39001e3c42000e7c2038717af0d33c32319ad591Reference added —https://git.kernel.org/stable/c/4bafcc43baf7bcf93566394dbd15726b5b456b7aReference added —https://git.kernel.org/stable/c/767146637efc528b5e3d31297df115e85a2fd362Reference added —https://git.kernel.org/stable/c/80ee5054435a11c87c9a4f30f1ff750080c96416Reference added —https://git.kernel.org/stable/c/98db42191329c679f4ca52bec0b319689e1ad8cbReference added —https://git.kernel.org/stable/c/b3c0f553820516ad4b62a9390ecd28d6f73a7b13Reference added —https://git.kernel.org/stable/c/ccd1108b16ab572d9bf635586b0925635dbd6bbcReference added —https://lists.debian.org/debian-lts-announce/2024/06/msg00017.htmlReference added —https://lists.debian.org/debian-lts-announce/2024/06/msg00020.htmlReference removed https://git.kernel.org/stable/c/014a807f1cc9c9d5173c1cd935835553b00d211c—Reference removed https://git.kernel.org/stable/c/39001e3c42000e7c2038717af0d33c32319ad591—Reference removed https://git.kernel.org/stable/c/4bafcc43baf7bcf93566394dbd15726b5b456b7a—Reference removed https://git.kernel.org/stable/c/767146637efc528b5e3d31297df115e85a2fd362—Reference removed https://git.kernel.org/stable/c/80ee5054435a11c87c9a4f30f1ff750080c96416—Reference removed https://git.kernel.org/stable/c/98db42191329c679f4ca52bec0b319689e1ad8cb—Reference removed https://git.kernel.org/stable/c/b3c0f553820516ad4b62a9390ecd28d6f73a7b13—Reference removed https://git.kernel.org/stable/c/ccd1108b16ab572d9bf635586b0925635dbd6bbc—Reference removed https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html—Reference removed https://lists.debian.org/debian-lts-announce/2024/06/msg00020.html—Reference type removed https://git.kernel.org/stable/c/014a807f1cc9c9d5173c1cd935835553b00d211c Types: Patch—Reference type removed https://git.kernel.org/stable/c/39001e3c42000e7c2038717af0d33c32319ad591 Types: Patch—Reference type removed https://git.kernel.org/stable/c/4bafcc43baf7bcf93566394dbd15726b5b456b7a Types: Patch—Reference type removed https://git.kernel.org/stable/c/767146637efc528b5e3d31297df115e85a2fd362 Types: Patch—Reference type removed https://git.kernel.org/stable/c/80ee5054435a11c87c9a4f30f1ff750080c96416 Types: Patch—Reference type removed https://git.kernel.org/stable/c/98db42191329c679f4ca52bec0b319689e1ad8cb Types: Patch—Reference type removed https://git.kernel.org/stable/c/b3c0f553820516ad4b62a9390ecd28d6f73a7b13 Types: Patch—Reference type removed https://git.kernel.org/stable/c/ccd1108b16ab572d9bf635586b0925635dbd6bbc Types: Patch—Reference type removed https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html Types: Mailing List—Reference type removed https://lists.debian.org/debian-lts-announce/2024/06/msg00020.html Types: Mailing List—Source identifier: af854a3a-2127-422b-91ae-364da2661108
Record modifiedSiemens ADP
Show 3 original changes
Individual changes of this event as published by NVD Type Action Before After Affected versions (publisher) added —Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2024/26xxx/CVE-2024-26851.json">CVE-2024-26851</a>Reference added —https://cert-portal.siemens.com/productcert/html/ssa-265688.htmlReference removed https://cert-portal.siemens.com/productcert/html/ssa-265688.html—Source identifier: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
Record modifiedLinux
CVSS V3.1: AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Show the original change
Individual changes of this event as published by NVD Type Action Before After CVSS added —AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HSource identifier: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
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<a href="https://intel.neosec.eu/en/cve/CVE-2024-26851"><img src="https://intel.neosec.eu/badge/cve/CVE-2024-26851.svg?lang=en" alt="CVE-2024-26851 – NEOSEC Intel" height="20"></a>