SB2017042851 - Fedora 25 update for kernel 



SB2017042851 - Fedora 25 update for kernel

Published: April 28, 2017 Updated: April 24, 2025

Security Bulletin ID SB2017042851
Severity
Medium
Patch available
YES
Number of vulnerabilities 2
Exploitation vector Adjecent network
Highest impact Code execution

Breakdown by Severity

Medium 50% Low 50%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 2 secuirty vulnerabilities.


1) Heap-based buffer overflow (CVE-ID: CVE-2017-7477)

The vulnerability allows a remote attacker on the local network execute arbitrary code on the target system.

The weakness exists due to heap-based buffer overflow in the skb_to_sgvec() function in the MACsec driver. A remote attacker can use a MAX_SKB_FRAGS+1 size in conjunction with the NETIF_F_FRAGLIST feature, trigger memory corruption and execute arbitrary code with root privileges.

Successful exploitation of the vulnerability results in arbitrary code execution.

2) Security restrictions bypass (CVE-ID: CVE-2016-9604)

The vulnerability allows a local attacker to write arbitrary files on the target system.

The weakness exists due to root can gain direct access to an internal keyring, such as '.dns_resolver' or '.builtin_trusted_keys' upstream, by joining it as its session keyring. A local attacker can bypass module signature verification by adding a new public key of its own devising to the keyring.

Remediation

Install update from vendor's website.