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TI-2025-15627 Aliases CVE-2025-21670GHSA-9w9r-vq29-w437

vsock/bpf: return early if transport is not assigned

Priority LOW 24CWE-476Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 2 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-476.

Summary

In the Linux kernel, the following vulnerability has been resolved: vsock/bpf: return early if transport is not assigned Some of the core functions can only be called if the transport has been assigned. As Michal reported, a socket might have the transport at NULL, for example after a failed connect(), causing the following trace: BUG: kernel NULL pointer dereference, address: 00000000000000a0 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 12faf8067 P4D 12faf8067 PUD 113670067 PMD 0 Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 15 UID: 0 PID: 1198 Comm: a.out Not tainted 6.13.0-rc2+ RIP: 0010:vsock_connectible_has_data+0x1f/0x40 Call Trace: vsock_bpf_recvmsg+0xca/0x5e0 sock_recvmsg+0xb9/0xc0 __sys_recvfrom+0xb3/0x130 __x64_sys_recvfrom+0x20/0x30 do_syscall_64+0x93/0x180 entry_SYSCALL_64_after_hwframe+0x76/0x7e So we need to check the `vsk->transport` in vsock_bpf_recvmsg(), especially for connected sockets (stream/seqpacket) as we already do in __vsock_connectible_recvmsg().

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00226 13th percentileScored 2026-11-07
Fix Partial Linux (Linux): 6.6.74, 6.12.11, 6.13Red Hat: 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux6.4 and later6.6.74, 6.12.11, 6.13Patch availableCNA
  • Linux VendorLinux Affected 6.4 and later Fixed in 6.6.74, 6.12.11, 6.13 Patch available CNA

CPE configurations NVD · 8

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*6.4 to before 6.6.74; 6.7 to before 6.12.11VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:*6.13 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.13:rc2:*:*:*:*:*:*6.13 rc2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.13:rc3:*:*:*:*:*:*6.13 rc3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.13:rc4:*:*:*:*:*:*6.13 rc4VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.13:rc5:*:*:*:*:*:*6.13 rc5VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.13:rc6:*:*:*:*:*:*6.13 rc6VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.13:rc7:*:*:*:*:*:*6.13 rc7VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 6.4 to before 6.6.74; 6.7 to before 6.12.11 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:* Versions 6.13 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.13:rc2:*:*:*:*:*:* Versions 6.13 rc2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.13:rc3:*:*:*:*:*:* Versions 6.13 rc3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.13:rc4:*:*:*:*:*:* Versions 6.13 rc4 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.13:rc5:*:*:*:*:*:* Versions 6.13 rc5 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.13:rc6:*:*:*:*:*:* Versions 6.13 rc6 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.13:rc7:*:*:*:*:*:* Versions 6.13 rc7 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 6.6.74, 6.12.11, 6.13

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix planned: Will not fix
Red Hat Enterprise Linux 9AffectedNo fix planned: Will not fix
Not affected: 3 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-21670
  2. 2026-10-03 Alias added: GHSA-9w9r-vq29-w437

References

  • 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-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
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources