CVE-2026-31683

CVE-2026-31683 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: batman-adv: avoid OGM aggregation when skb tailroom is insufficient When OGM aggregation state is toggled at runtime, an existing forwarded packet may have been allocated with only packet_len bytes, while a later packet can still be selected for aggregation. Appending in this case can hit skb_put overflow conditions. Reject aggregation when the target skb tailroom cannot accommodate the new packet. The caller then falls back to creating a new forward packet instead of appending.

Frequently asked questions

What is CVE-2026-31683?
In the Linux kernel, the following vulnerability has been resolved: batman-adv: avoid OGM aggregation when skb tailroom is insufficient When OGM aggregation state is toggled at runtime, an existing forwarded packet may have been allocated with only packet_len bytes, while a later packet can still be selected for aggregation. Appending in this case can hit skb_put overflow conditions. Reject aggregation when the target skb tailroom cannot accommodate the new packet. The caller then falls back to creating a new forward packet instead of appending.
How severe is CVE-2026-31683?
CVE-2026-31683 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-31683 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-31683?
CVE-2026-31683 primarily affects Linux Linux Kernel. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-31683?
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-2026-31683 have an EU (EUVD) identifier?
Yes. CVE-2026-31683 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-25650.
When was CVE-2026-31683 published?
CVE-2026-31683 was published on 2026-04-25 and last updated on 2026-06-17.

References

Affected products (5)

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