Critical severity · published Apr 24, 2026
CVE-2026-31659
batman-adv: reject oversized global TT response buffers
9.8
CVSS
0.4%
EPSS
No
On KEV
Description
In the Linux kernel, the following vulnerability has been resolved: batman-adv: reject oversized global TT response buffers batadv_tt_prepare_tvlv_global_data() builds the allocation length for a global TT response in 16-bit temporaries. When a remote originator advertises a large enough global TT, the TT payload length plus the VLAN header offset can exceed 65535 and wrap before kmalloc(). The full-table response path still uses the original TT payload length when it fills tt_change, so the wrapped allocation is too small and batadv_tt_prepare_tvlv_global_data() writes past the end of the heap object before the later packet-size check runs. Fix this by rejecting TT responses whose TVLV value length cannot fit in the 16-bit TVLV payload length field.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 36% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
3.13.1 before 5.10.253; 5.11 before 5.15.203; 5.16 before 6.1.169; 6.2 before 6.6.135; 6.7 before 6.12.82; 6.13 before 6.18.23; +9 more · source: NVD
LI
Linux · Linux
7ea7b4a142758deaf46c1af0ca9ceca6dd55138b before 7e5d007e0df946bffb8542fb112e0044014a5897; 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b before 2997f4bd1f982e7013709946e00be89b507693fa; 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b before 95c71365a2222908441b54d6f2c315e0c79fcec3; 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b before 69d61639bc7e963c3b645e570279d731e7c89062; 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b before f970646b9a39539d1bac86822ac78b5915455ea9; 7ea7b4a142758deaf46c1af0ca9ceca6dd55138b before de6c1dc3c7d01a152607e6fcecee4d5288283f10; +3 more · source: vendor