High severity · published Jul 19, 2026
CVE-2026-64088
batman-adv: tt: fix negative tt_buff_len
8.8
CVSS
0.3%
EPSS
No
On KEV
Description
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().
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 21% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
3.1 before 5.10.258; 5.11 before 5.15.209; 5.16 before 6.1.175; 6.2 before 6.6.142; 6.7 before 6.12.92; 6.13 before 6.18.34; +5 more · source: NVD
LI
Linux · Linux
a73105b8d4c765d9ebfb664d0a66802127d8e4c7 before 4c4c2f340f4c27373bfcac8dc5032ce7bb474e47; a73105b8d4c765d9ebfb664d0a66802127d8e4c7 before 33e5ede7ce6d92e531920d4bbd6d3e18ef1c6430; a73105b8d4c765d9ebfb664d0a66802127d8e4c7 before 3c96dff00998314983b68a3e7caac07a66ebe496; a73105b8d4c765d9ebfb664d0a66802127d8e4c7 before 32edd2a28e112064020a2f319a8cb8a9e5a09767; a73105b8d4c765d9ebfb664d0a66802127d8e4c7 before 4dab98961426d0cf6a1599cda6950b7596ca2fcd; a73105b8d4c765d9ebfb664d0a66802127d8e4c7 before 730de8733dd90f70d7580a9b329b971f8e1474a2; +3 more · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-64088
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-64088
Patch
https://git.kernel.org/stable/c/32edd2a28e112064020a2f319a8cb8a9e5a09767
Patch
https://git.kernel.org/stable/c/33e5ede7ce6d92e531920d4bbd6d3e18ef1c6430
Patch
https://git.kernel.org/stable/c/3c96dff00998314983b68a3e7caac07a66ebe496
Patch
https://git.kernel.org/stable/c/4c4c2f340f4c27373bfcac8dc5032ce7bb474e47
Patch
https://git.kernel.org/stable/c/4dab98961426d0cf6a1599cda6950b7596ca2fcd
Patch
https://git.kernel.org/stable/c/730de8733dd90f70d7580a9b329b971f8e1474a2
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