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CVE · referencelatest edition

Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2024-26851MEDIUM
Linux Linux — netfilter: nf_conntrack_h323: Add protection for bmp length out of range
  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   L   L   L   N  U  N  N  H    5.5   .0073   51.6     —
AFFECTED
  Product  Versions                                    Fixed
  Linux    5e35941d990123f155b02d5663e51a24f816b6f3 –  —
  Linux    2.6.17 –                                    4.19.310
TIMELINE
  Feb 19  Reserved by Linux
  Apr 17  Published (CNA: Linux)
  Aug 4   RESCORED — CVE-2024-26851 (Linux). CVSS 7.5 → 5.5 (NVD).
CWE-787 · CNA: Linux · CVSS v3.1 · 11 references · NVD status: Modified

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.

Lifecycle

Complete event history — 3 events, chronological
DateEventDetail
February 19, 2024ReservedReserved by Linux
April 17, 2024PublishedPublished (CNA: Linux)
August 4, 2026RESCOREDRESCORED — CVE-2024-26851 (Linux). CVSS 7.5 → 5.5 (NVD).

Affected

Affected products and packages — 2 rows
VendorProduct / PackageEcosystemVersion introducedFixed
LinuxLinux5e35941d990123f155b02d5663e51a24f816b6f3
LinuxLinux2.6.174.19.310

Weaknesses

CWE-787

References (11)

Related

Authoritative record: CVE-2024-26851 at cve.org

Vendors: linux

Weaknesses: CWE-787

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2024-26851 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.