CVE-2026-43495

CVE-2026-43495 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-125.

Key facts

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.

Frequently asked questions

What is CVE-2026-43495?
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.
How severe is CVE-2026-43495?
CVE-2026-43495 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-43495 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (19th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-43495?
CVE-2026-43495 primarily affects Linux Linux Kernel. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-43495?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-43495 have an EU (EUVD) identifier?
Yes. CVE-2026-43495 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31271.
When was CVE-2026-43495 published?
CVE-2026-43495 was published on 2026-05-21 and last updated on 2026-06-26.

References

Affected products (3)

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