Read the docs
TI-2026-75728 Aliases CVE-2026-98600GHSA-hpgr-cqmv-php2

Missing length check in Linux kernel RFCOMM accepts short frames

Priority LOW 22Published · Updated

Key facts

Attack vector
—
Privileges required
—
User interaction
—
Attack complexity
—
Impact type
—
Confidentiality · integrity · availability
—
Fix status
Partial Red Hat: 1 without a fix

No CVSS vector from any source. Fix status from CNA and Red Hat.

Summary

The Linux kernel Bluetooth RFCOMM implementation affects Linux kernel versions in the listed commit ranges and from 7.2 before 7.2.9. The rfcomm_recv_frame() function accepts a 4-byte frame with the EA bit set to 0 even though it needs at least 5 bytes, so the FCS trim leaves a 3-byte header in the buffer. That header is then handled as application payload or as a multiplexer control command on DLCI 0. The sources do not list CISA KEV inclusion or public exploitation.

Written with Claude Haiku 5.5 from the sources below · 2026-10-30

Description from the CNA

In the Linux kernel, the following vulnerability has been resolved: Bluetooth: RFCOMM: Reject short EA=0 frames in rfcomm_recv_frame() While rfcomm_recv_frame() verifies that skb->len is at least sizeof(*hdr) + 1 (4 bytes: 3-byte header + 1-byte FCS), an RFCOMM frame with an extended 2-byte length field (!__test_ea(hdr->len)) has a 4-byte header plus a 1-byte FCS (5 bytes minimum, sizeof(*hdr) + 2). When a 4-byte RFCOMM frame with EA == 0 arrives: 1. The initial skb->len < sizeof(*hdr) + 1 check passes (4 < 4 is false). 2. Trimming the FCS byte decrements skb->len to 3. 3. If __check_fcs() succeeds, skb_pull(skb, 4) fails (4 > 3) and returns NULL without advancing skb->data. 4. Because the return value of skb_pull() is ignored, the un-pulled 3-byte struct rfcomm_hdr remains at skb->data and is either queued as application payload via rfcomm_recv_data() or parsed as a multiplexer control command via rfcomm_recv_mcc() on DLCI 0. Fix this by extending the length check in rfcomm_recv_frame() to also require skb->len >= sizeof(*hdr) + 2 when !__test_ea(hdr->len).

Why it matters now

EPSS 0.00177 7th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.12.112, 6.18.55, 7.2.9 +1Red Hat: 1 without a fix

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux6.12.111 to before 6.12.112; 6.18.53 to before 6.18.556.12.112, 6.18.55Patch availableCNA
LinuxLinux7.2 and later6.12.112, 6.18.55, 7.2.9, 7.3Patch availableCNA
  • Linux VendorLinux Affected 6.12.111 to before 6.12.112; 6.18.53 to before 6.18.55 Fixed in 6.12.112, 6.18.55 Patch available CNA
  • Linux VendorLinux Affected 7.2 and later Fixed in 6.12.112, 6.18.55, 7.2.9, 7.3 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*——Linux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions — — ·Linux

Remediation

Linux kernel 6.12.112, 6.18.55, 7.2.9 and 7.3 contain the fix. Red Hat Enterprise Linux 6 is affected and has no fix planned.

Written with Claude Haiku 5.5 from the sources below · 2026-10-30

  • Fix · CNA Linux (Linux) Fixed in 6.12.112, 6.18.55
  • Fix · CNA Linux (Linux) Fixed in 6.12.112, 6.18.55, 7.2.9, 7.3

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Not affected: 6 products
  • Red Hat Enterprise Linux 10
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9
  • Red Hat OpenShift Container Platform 4
  • Red Hat OpenShift Container Platform 5

Timeline

  1. 2026-10-18 Threatist record created from CVE-2026-98600
  2. 2026-10-18 Alias added: GHSA-hpgr-cqmv-php2
  3. 2026-10-19 Fix available: Linux/[email protected] · CNA
  4. 2026-10-20 Affected versions changed · Red Hat
  5. 2026-10-20 CVSS score added · Red Hat
  6. 2026-10-30 Affected versions changed · Red Hat

References

Other 8

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2021-02452 Incorrect authorization in Ubuntu linux kernel KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
See all 21741 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences