CVE-2025-39839

Medium

Elevated severity or exploit probability.

CVSS base

8.8 HIGH

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS — probability of exploitation (30 days)

0.3%

17.2th percentile

CISA KEV

Not listed

Weakness / dates

CWE-125

Published 2025-09-19 · modified 2026-07-30

CVSS breakdown

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack Vector	A	Adjacent
Attack Complexity	L	Low
Privileges Required	N	None
User Interaction	N	None
Scope	U	Unchanged
Confidentiality	H	High
Integrity	H	High
Availability	H	High

Timeline

2025-09-19 — Published (NVD)
2026-07-30 — Last modified (NVD)

Description

In the Linux kernel, the following vulnerability has been resolved: batman-adv: fix OOB read/write in network-coding decode batadv_nc_skb_decode_packet() trusts coded_len and checks only against skb->len. XOR starts at sizeof(struct batadv_unicast_packet), reducing payload headroom, and the source skb length is not verified, allowing an out-of-bounds read and a small out-of-bounds write. Validate that coded_len fits within the payload area of both destination and source sk_buffs before XORing.

Affected

debian linux

References

Official: NVD · CVE.org