dbcve.org
Linux KernelOperating system · Linux

CVE-2026-53078

HIGH · 7.8 CVSS v3.1 Published 2026-06-24
Fix available
A fix is available. Upgrade to 5.5 / 5.8 or later.
See remediation →
80/100
Remediation priority · High
Zero-click 8 weeks old

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix same-register dst/src OOB read and pointer leak in sock_ops When a BPF sock_ops program accesses ctx fields with dst_reg == src_reg, the SOCK_OPS_GET_SK() and SOCK_OPS_GET_FIELD() macros fail to zero the destination register in the !fullsock / !locked_tcp_sock path. Both macros borrow a temporary register to check is_fullsock / is_locked_tcp_sock when dst_reg == src_reg, because dst_reg holds the ctx pointer. When the check is false (e.g., TCP_NEW_SYN_RECV state with a request_sock), dst_reg should be zeroed but is not, leaving the stale ctx pointer: - SOCK_OPS_GET_SK: dst_reg retains the ctx pointer, passes NULL checks as PTR_TO_SOCKET_OR_NULL, and can be used as a bogus socket pointer, leading to stack-out-of-bounds access in helpers like bpf_skc_to_tcp6_sock(). - SOCK_OPS_GET_FIELD: dst_reg retains the ctx pointer which the verifier believes is a SCALAR_VALUE, leaking a kernel pointer. Fix both macros by: - Changing JMP_A(1) to JMP_A(2) in the fullsock path to skip the added instruction. - Adding BPF_MOV64_IMM(si->dst_reg, 0) after the temp register restore in the !fullsock path, placed after the restore because dst_reg == src_reg means we need src_reg intact to read ctx->temp.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

In Linux kernel BPF sock_ops, when dst_reg equals src_reg, the SOCK_OPS_GET_SK() and SOCK_OPS_GET_FIELD() macros fail to zero the destination register in the !fullsock path after borrowing it for a temporary check. This leaves a stale ctx pointer that passes NULL checks as PTR_TO_SOCKET_OR_NULL, enabling OOB stack access, or is misinterpreted by the verifier as a SCALAR_VALUE, causing a kernel pointer leak.

MitigationApply the kernel patch which adds BPF_MOV64_IMM(si->dst_reg, 0) to zero the dst_reg in the !fullsock path and adjusts the jump offset in the fullsock path to skip this instruction.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Linux KernelOperating system
Affected:>= 5.4.61, < 5.5>= 5.7.18, < 5.8>= 5.8.4, < 5.9>= 5.9.1, < 7.0.10= 5.9

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check kernel version
    Run 'uname -r' to get the running kernel version and compare against the version that includes the patch for this CVE
    Affected if The kernel version is older than the patched version containing the fix for the SOCK_OPS_GET_SK/SOCK_OPS_GET_FIELD register zeroing issue
  2. Verify BPF sock_ops program usage
    Run 'bpftool prog list | grep -i sock_ops' or check /sys/kernel/debug/tracing/events/bpf_trace/ for sock_ops related entries
    Affected if BPF sock_ops programs are loaded and running on the system
  3. Check for loaded BPF programs with sock_ops type
    Use 'bpftool prog show' and filter for program_type sock_ops, or check /proc/sys/kernel/bpf_stats_enabled if available
    Affected if Any BPF sock_ops programs are currently loaded in the kernel
  4. Inspect BPF sock_map or sockhash usage
    Run 'bpftool map list' to see if sock_maps or sockhash maps are present, as these are commonly used with sock_ops programs
    Affected if sock_maps or sockhash maps are actively used in conjunction with sock_ops programs

The system is affected if it runs an unpatched kernel and has active BPF sock_ops programs or sock_maps/sockhash maps in use.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Upgrade available Upgrade to 5.5 / 5.8 / 5.9 or later
Fixed in 5.55.85.9
Interim mitigation

Apply the kernel patch which adds BPF_MOV64_IMM(si->dst_reg, 0) to zero the dst_reg in the !fullsock path and adjusts the jump offset in the fullsock path to skip this instruction.

Fix this in Linux Kernel Scoped from the published advisory
  • Consultation3.0 h
  • Implementation4.0 h
  • Testing6.0 h
  • Review / QA3.0 h
16.0 hours of engineering $2,760
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,416.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-53078 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-53078 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data