CVE-2026-64089
In the Linux kernel, the following vulnerability has been resolved: batman-adv: tt: fix negative last_changeset_len batadv_piv_tt::last_changeset_len len was declared as s16, but the field is never intended to hold a negative value.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.55%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
In the Linux kernel, the following vulnerability has been resolved: batman-adv: tt: fix negative last_changeset_len batadv_piv_tt::last_changeset_len 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_my_tt_response(), last_changeset_len is temporarily widened to s32. The incorrectly negative s16 value propagates into the s32, causing batadv_tt_prepare_tvlv_local_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_my_tt_response().
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.55% probability · 44th percentile
- CISA KEV
- Not listed
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/179eb62506a02d00370bd6478898cb632e10986cPatch
- https://git.kernel.org/stable/c/22d59c72f4a47ffec121d0610f70d0d70c3c11c8Patch
- https://git.kernel.org/stable/c/55dc41fe8821e9a849e147255ad572bc933a9d15Patch
- https://git.kernel.org/stable/c/6314089acf0ddf64376fdc0b1420695504c73f52Patch
- https://git.kernel.org/stable/c/c424e8519ac78eac5d9f4eecf06208a0d619ec14Patch
- https://git.kernel.org/stable/c/d29abf70c665730e249d2ec8e1402095ae26bceePatch
- https://git.kernel.org/stable/c/eb235472b52ef36981c5aad330485eaf2382c53bPatch
- https://git.kernel.org/stable/c/fc92cdfcb295cefa4344d71a527d61b638b7bfc4Patch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.