CVE-2026-31659
batman-adv: reject oversized global TT response buffers
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.
INFO
Published Date :
April 24, 2026, 3:16 p.m.
Last Modified :
April 24, 2026, 3:16 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2026-31659
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Update the Linux kernel.
- Reject TT responses with invalid TVLV lengths.
- Ensure TT payload length fits 16-bit field.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-31659.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-31659 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-31659
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-31659 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-31659 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Apr. 24, 2026
Action Type Old Value New Value Added 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. Added Reference https://git.kernel.org/stable/c/2997f4bd1f982e7013709946e00be89b507693fa Added Reference https://git.kernel.org/stable/c/3a359bf5c61d52e7f09754108309d637532164a6 Added Reference https://git.kernel.org/stable/c/69d61639bc7e963c3b645e570279d731e7c89062 Added Reference https://git.kernel.org/stable/c/7e5d007e0df946bffb8542fb112e0044014a5897 Added Reference https://git.kernel.org/stable/c/95c71365a2222908441b54d6f2c315e0c79fcec3 Added Reference https://git.kernel.org/stable/c/cf2199171ef799ca7270019125f4a91bd20ad4d9 Added Reference https://git.kernel.org/stable/c/de6c1dc3c7d01a152607e6fcecee4d5288283f10 Added Reference https://git.kernel.org/stable/c/f970646b9a39539d1bac86822ac78b5915455ea9