Linux KernelOperating system · Linux

CVE-2023-52778

MEDIUM · 5.5 CVSS v3.1 Published 2024-05-21

Fix available

A fix is available. Upgrade to 6.1.64 / 6.5.13 or later.

See remediation →

57/100

Remediation priority · Elevated

Zero-click Patch available

Official description

NVD · unedited

In the Linux kernel, the following vulnerability has been resolved: mptcp: deal with large GSO size After the blamed commit below, the TCP sockets (and the MPTCP subflows) can build egress packets larger than 64K. That exceeds the maximum DSS data size, the length being misrepresent on the wire and the stream being corrupted, as later observed on the receiver: WARNING: CPU: 0 PID: 9696 at net/mptcp/protocol.c:705 __mptcp_move_skbs_from_subflow+0x2604/0x26e0 CPU: 0 PID: 9696 Comm: syz-executor.7 Not tainted 6.6.0-rc5-gcd8bdf563d46 #45 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014 netlink: 8 bytes leftover after parsing attributes in process `syz-executor.4'. RIP: 0010:__mptcp_move_skbs_from_subflow+0x2604/0x26e0 net/mptcp/protocol.c:705 RSP: 0018:ffffc90000006e80 EFLAGS: 00010246 RAX: ffffffff83e9f674 RBX: ffff88802f45d870 RCX: ffff888102ad0000 netlink: 8 bytes leftover after parsing attributes in process `syz-executor.4'. RDX: 0000000080000303 RSI: 0000000000013908 RDI: 0000000000003908 RBP: ffffc90000007110 R08: ffffffff83e9e078 R09: 1ffff1100e548c8a R10: dffffc0000000000 R11: ffffed100e548c8b R12: 0000000000013908 R13: dffffc0000000000 R14: 0000000000003908 R15: 000000000031cf29 FS: 00007f239c47e700(0000) GS:ffff88811b200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f239c45cd78 CR3: 000000006a66c006 CR4: 0000000000770ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 PKRU: 55555554 Call Trace: <IRQ> mptcp_data_ready+0x263/0xac0 net/mptcp/protocol.c:819 subflow_data_ready+0x268/0x6d0 net/mptcp/subflow.c:1409 tcp_data_queue+0x21a1/0x7a60 net/ipv4/tcp_input.c:5151 tcp_rcv_established+0x950/0x1d90 net/ipv4/tcp_input.c:6098 tcp_v6_do_rcv+0x554/0x12f0 net/ipv6/tcp_ipv6.c:1483 tcp_v6_rcv+0x2e26/0x3810 net/ipv6/tcp_ipv6.c:1749 ip6_protocol_deliver_rcu+0xd6b/0x1ae0 net/ipv6/ip6_input.c:438 ip6_input+0x1c5/0x470 net/ipv6/ip6_input.c:483 ipv6_rcv+0xef/0x2c0 include/linux/netfilter.h:304 __netif_receive_skb+0x1ea/0x6a0 net/core/dev.c:5532 process_backlog+0x353/0x660 net/core/dev.c:5974 __napi_poll+0xc6/0x5a0 net/core/dev.c:6536 net_rx_action+0x6a0/0xfd0 net/core/dev.c:6603 __do_softirq+0x184/0x524 kernel/softirq.c:553 do_softirq+0xdd/0x130 kernel/softirq.c:454 Address the issue explicitly bounding the maximum GSO size to what MPTCP actually allows.

Technical summary

dbcve analysis

A detailed technical summary for this CVE is being prepared.

Affected products & versions

NVD · CPE data

Linux KernelOperating system

Affected:>= 5.19, < 6.1.64>= 6.2, < 6.5.13>= 6.6, < 6.6.3= 6.7

CVSS breakdown

From the vector

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

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

Remediation

dbcve · scoped

Upgrade available Upgrade to 6.1.64 / 6.5.13 / 6.6.3 or later

Fixed in 6.1.646.5.136.6.3

Vendor patch git.kernel.org →

Recommended fix High confidence

Linux Kernel 6.8 or the appropriate fixed version for your branch (6.1.64+, 6.5.13+, or 6.6.3+)

Check current kernel version with `uname -r` to confirm if the system is running an affected version
Identify the appropriate upgrade target based on your current kernel branch: for 6.1.x upgrade to >= 6.1.64, for 6.2.x-6.5.x upgrade to >= 6.5.13, for 6.6.x upgrade to >= 6.6.3, for 6.7.x upgrade to >= 6.8 or later
Update the kernel package using the distribution's package manager (e.g., `apt-get update && apt-get install linux-image-*` for Debian/Ubuntu, or `yum update kernel` for RHEL/CentOS)
Reboot the system to load the new kernel
Verify the new kernel version is running with `uname -r` and confirm it is a fixed version

Caveat Kernel upgrades may require system reboot and could have compatibility impacts with out-of-tree kernel modules or specific hardware drivers; test in non-production environment first

Generated from the published advisory — verify against the referenced sources before acting.

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $1,600. Get the upgrade done

Scan for this in your stack

Free · runs locally

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References

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2023-52778 in production — separate from our analysis above.

Notes0 Guidelines

Know something about CVE-2023-52778?

The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.

The version that genuinely resolved it — not the one the vendor claimed
A config change or rule that shut the vector down
A gotcha in the upgrade path that cost you an afternoon

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

At a glance

A fix existsUpgrade to 6.1.64 / 6.5.13 or later

Severity 5.5 Medium

Exploit likelihood EPSS, next 30 days 0.2%

Affects: Linux Kernel

Remediation

Need this fixed?

Get a fix

Estimated effortfrom ~9 hrs

ComplexityModerate

Typical engagementfrom $1,600

What a fix involves

We scope it with you and confirm a fixed quote
A specialist builds a reviewed fix
You deploy it to staging first
Optional re-test once it’s live

We specialise in CVE remediation. Send your environment and we’ll scope CVE-2023-52778 and return a fixed quote.

You’ll deal with our team directly and deploy the reviewed fix to staging first — never straight to production.

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.

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.

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.

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.

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.

Scan for this in your stack

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

Practitioner notes

No notes yet

Official description

Technical summary

Affected products & versions

CVSS breakdown

Remediation

References