CVE-2018-6551: The malloc implementation in the GNU C Library (aka glibc or libc6), from version 2.24 to 2.26 on powerpc, and only in version 2.26 on i386, did not properly…

PriorityP338critical9.8CVSS 3.0

AVNACLPRNUINSUCHIHAH

EPSS

2.19%

80.5th percentile

The malloc implementation in the GNU C Library (aka glibc or libc6), from version 2.24 to 2.26 on powerpc, and only in version 2.26 on i386, did not properly handle malloc calls with arguments close to SIZE_MAX and could return a pointer to a heap region that is smaller than requested, eventually leading to heap corruption.

Affected

6 ranges

Vendor	Product	Version range	Fixed in
debian	glibc	< glibc 2.27-1 (bookworm)	glibc 2.27-1 (bookworm)
gnu	glibc	>= 0 < 2.27-1	2.27-1
gnu	glibc	>= 0 < 2.27-1	2.27-1
gnu	glibc	>= 0 < 2.27-1	2.27-1
gnu	glibc	>= 0 < 2.27-1	2.27-1
gnu	glibc	2.24 – 2.26	—

CVSS provenance

nvdv3.09.8CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P

osv9.8CRITICAL

vendor_debian9.8CRITICAL

vendor_redhat9.8CRITICAL

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