CVE Catalog

CVE-2025-39839

HighCVSS 8.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.24%

15th percentile - higher than 15% of all known CVEs

Summary

In the Linux kernel, the batman-adv module has an out-of-bounds read/write vulnerability in the network-coding decode function. The batadv_nc_skb_decode_packet function trusts coded_len and only checks skb->len, allowing out-of-bounds read and small write.

Risk Assessment

Risk of out-of-bounds buffer read or write, which could lead to information leak or system crash. An attacker could exploit this to destabilize the mesh network.

Recommendation

Apply the Linux kernel patch that adds validation of coded_len against the payload area of both sk_buffs. Update the system to a kernel version containing the fix.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

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.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS