Linux: Out-of-bounds Read
CVE-2026-53131 is a critical-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 9.4 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 4435888e1bf139d2bfe5911643d4217382136743, 063f43361e884acd7300790e90194430275d0d0c, 726abf97566867f808fec9d8a408eb9698bd570a as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.43% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update Linux to 4435888e1bf139d2bfe5911643d4217382136743 or 063f43361e884acd7300790e90194430275d0d0c or 726abf97566867f808fec9d8a408eb9698bd570a or 367abcacc13a8e2e7624408b7f593bd1e60e49d9, whichever matches your release line, or a later version.
- Update Linux Kernel to 5.15.210 or 6.1.176 or 6.6.143 or 6.12.94, whichever matches your release line, or a later version.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 4435888e1bf139d2bfe5911643d4217382136743; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 063f43361e884acd7300790e90194430275d0d0c; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 726abf97566867f808fec9d8a408eb9698bd570a; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 367abcacc13a8e2e7624408b7f593bd1e60e49d9; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 5d634afb8b83b49de562792fd0d047416a43bd4d; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, cea435ea7e868ea6fdf039bc4f2090c1d829b556; 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 up to, but not including, 62443dc21114c0bbc476fa62973db89743f2f137; 2.6.12 | 4435888e1bf139d2bfe5911643d4217382136743, 063f43361e884acd7300790e90194430275d0d0c, 726abf97566867f808fec9d8a408eb9698bd570a, 367abcacc13a8e2e7624408b7f593bd1e60e49d9, 5d634afb8b83b49de562792fd0d047416a43bd4d, cea435ea7e868ea6fdf039bc4f2090c1d829b556 |
| Siemens | SIMATIC S7-1500 TM MFP - GNU/Linux subsystem | all versions | Not stated |
| Linux | Linux Kernel | 2.6.12.1 up to, but not including, 5.15.210; 5.16 up to, but not including, 6.1.176; 6.2 up to, but not including, 6.6.143; 6.7 up to, but not including, 6.12.94; 6.13 up to, but not including, 6.18.36; 6.19 up to, but not including, 7.0.13; 2.6.12 | 5.15.210, 6.1.176, 6.6.143, 6.12.94, 6.18.36, 7.0.13 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- LowLimited modification of data is possible.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:H. Scored by CNA.
Official description
In the Linux kernel, the following vulnerability has been resolved: netfilter: require Ethernet MAC header before using eth_hdr() `ip6t_eui64`, `xt_mac`, the `bitmap:ip,mac`, `hash:ip,mac`, and `hash:mac` ipset types, and `nf_log_syslog` access `eth_hdr(skb)` after either assuming that the skb is associated with an Ethernet device or checking only that the `ETH_HLEN` bytes at `skb_mac_header(skb)` lie between `skb->head` and `skb->data`. Make these paths first verify that the skb is associated with an Ethernet device, that the MAC header was set, and that it spans at least a full Ethernet header before accessing `eth_hdr(skb)`.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Out-of-bounds Read
The product reads data past the end, or before the beginning, of the intended buffer.
How developers prevent this class of flaw
- Use a language that provides appropriate memory abstractions.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- git.kernel.org/stable/c/063f43361e884acd7300790e90194430275d0d0c
- git.kernel.org/stable/c/367abcacc13a8e2e7624408b7f593bd1e60e49d9
- git.kernel.org/stable/c/4435888e1bf139d2bfe5911643d4217382136743
- git.kernel.org/stable/c/5d634afb8b83b49de562792fd0d047416a43bd4d
- git.kernel.org/stable/c/62443dc21114c0bbc476fa62973db89743f2f137
- git.kernel.org/stable/c/726abf97566867f808fec9d8a408eb9698bd570a
- git.kernel.org/stable/c/cea435ea7e868ea6fdf039bc4f2090c1d829b556
Other references
Recent Out-of-bounds Read vulnerabilities
- 7.5 High severity
- 7.1 High severity
- 8.4 High severity
- 9.1 Critical severity
- 8.2 High severity
- 7.1 High severity
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