CVE-2018-14619

A flaw was found in the crypto subsystem of the Linux kernel before version kernel-4.15-rc4. The null skcipher was being dropped when each af_alg_ctx was freed instead of when the aead_tfm was freed. This can cause the null skcipher to be freed while it is still in use leading to a local user being able to crash the system or possibly escalate privileges.

Weakness

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory “belongs” to the code that operates on the new pointer.

Affected Software

Potential Mitigations

References

• http://www.securityfocus.com/bid/105200
• https://access.redhat.com/errata/RHSA-2018:2948
• https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-14619
• https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b32a7dc8aef1882fbf983eb354837488cc9d54dc
• https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2018-0013
• http://www.securityfocus.com/bid/105200
• https://access.redhat.com/errata/RHSA-2018:2948
• https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2018-14619
• https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b32a7dc8aef1882fbf983eb354837488cc9d54dc
• https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2018-0013