Linux: Out-of-bounds Read
CVE-2026-43495 is a high-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. The record lists versions 307c5d0f36a5c74042217136da5bfbd9f7504650, f94450ce5053b36002995b72d1fa1db3bb08c5bf, 9855e063e063158cc5bded576382599dc3133202 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 0.32% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux to 307c5d0f36a5c74042217136da5bfbd9f7504650 or f94450ce5053b36002995b72d1fa1db3bb08c5bf or 9855e063e063158cc5bded576382599dc3133202 or 2b56d7903ab804481f5233a259d5f341e9fd513c, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.1.176 or 6.6.140 or 6.12.88 or 6.18.30, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | da45d2566a1d4e260b894ff5d96be64b21c7fa79 up to, but not including, 307c5d0f36a5c74042217136da5bfbd9f7504650; da45d2566a1d4e260b894ff5d96be64b21c7fa79 up to, but not including, f94450ce5053b36002995b72d1fa1db3bb08c5bf; da45d2566a1d4e260b894ff5d96be64b21c7fa79 up to, but not including, 9855e063e063158cc5bded576382599dc3133202; da45d2566a1d4e260b894ff5d96be64b21c7fa79 up to, but not including, 2b56d7903ab804481f5233a259d5f341e9fd513c; da45d2566a1d4e260b894ff5d96be64b21c7fa79 up to, but not including, dd4f4c93c1488d7100b9964f2da4c8b3c29652f1; da45d2566a1d4e260b894ff5d96be64b21c7fa79 up to, but not including, 0e7c074cfcd9bd93765505f9eb8b42f03ed2a744; 5.19 | 307c5d0f36a5c74042217136da5bfbd9f7504650, f94450ce5053b36002995b72d1fa1db3bb08c5bf, 9855e063e063158cc5bded576382599dc3133202, 2b56d7903ab804481f5233a259d5f341e9fd513c, dd4f4c93c1488d7100b9964f2da4c8b3c29652f1, 0e7c074cfcd9bd93765505f9eb8b42f03ed2a744 |
| Linux | Linux Kernel | 5.19 up to, but not including, 6.1.176; 6.2 up to, but not including, 6.6.140; 6.7 up to, but not including, 6.12.88; 6.13 up to, but not including, 6.18.30; 6.19 up to, but not including, 7.0.7; 7.1 | 6.1.176, 6.6.140, 6.12.88, 6.18.30, 7.0.7 |
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
- AdjacentThe attacker must be on the same local network segment.
- 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
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA.
Official description
In the Linux kernel, the following vulnerability has been resolved: net: wwan: t7xx: validate port_count against message length in t7xx_port_enum_msg_handler t7xx_port_enum_msg_handler() uses the modem-supplied port_count field as a loop bound over port_msg->data[] without checking that the message buffer contains sufficient data. A modem sending port_count=65535 in a 12-byte buffer triggers a slab-out-of-bounds read of up to 262140 bytes. Add a sizeof(*port_msg) check before accessing the port message header fields to guard against undersized messages. Add a struct_size() check after extracting port_count and before the loop. In t7xx_parse_host_rt_data(), guard the rt_feature header read with a remaining-buffer check before accessing data_len, validate feat_data_len against the actual remaining buffer to prevent OOB reads and signed integer overflow on offset. Pass msg_len from both call sites: skb->len at the DPMAIF path after skb_pull(), and the validated feat_data_len at the handshake path.
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.
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- git.kernel.org/stable/c/0e7c074cfcd9bd93765505f9eb8b42f03ed2a744
- git.kernel.org/stable/c/2b56d7903ab804481f5233a259d5f341e9fd513c
- git.kernel.org/stable/c/307c5d0f36a5c74042217136da5bfbd9f7504650
- git.kernel.org/stable/c/9855e063e063158cc5bded576382599dc3133202
- git.kernel.org/stable/c/dd4f4c93c1488d7100b9964f2da4c8b3c29652f1
- git.kernel.org/stable/c/f94450ce5053b36002995b72d1fa1db3bb08c5bf
Other references
- openwall.com/lists/oss-security/2026/06/18/1Mailing List
Recent Out-of-bounds Read vulnerabilities
- 7.1 High severity
- 7.1 High severity
- 8.8 High severity
- 9.8 Critical severity
- 8.1 High severity
- 7.1 High severity
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