CVE-2026-64088
HighCVSS 8.8Exploitation Probability (EPSS)
Low risk20th percentile - higher than 20% of all known CVEs
Summary
In the Linux kernel's batman-adv module, a vulnerability was found due to incorrect typing of the `tt_buff_len` field as `s16` instead of `u16`. Values greater than 32767 wrap to negative numbers, causing full buffer allocation but only partial population, leaving the rest uninitialized.
Risk Assessment
The risk involves potential leakage of uninitialized kernel memory during TT (Translation Table) response processing in batman-adv mesh networks, which could allow an attacker to read sensitive information or destabilize the system.
Recommendation
Immediately update the Linux kernel to a version containing the fix that changes `tt_buff_len` to `u16`. Monitor official security advisories from your Linux distribution for the appropriate patch.
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- CVE-2026-80533Unknown
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Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: batman-adv: tt: fix negative tt_buff_len batadv_orig_node::tt_buff_len was declared as s16, but the field is never intended to hold a negative value. When a value greater than 32767 is assigned, it wraps to a negative signed integer. In batadv_send_other_tt_response(), tt_buff_len is temporarily widened to s32. The incorrectly negative s16 value propagates into the s32, causing batadv_tt_prepare_tvlv_global_data() to allocate a full sized buffer but populates only a small portion of it with the collected changeset. All remaining bits are kept uninitialized. Using an u16 avoids this type confusion and ensures that no (negative) sign extension is performed in batadv_send_other_tt_response().

