Buffer overflow in GNU Glibc

CVE-2017-18269

An SSE2-optimized memmove implementation for i386 in sysdeps/i386/i686/multiarch/memcpy-sse2-unaligned.S in the GNU C Library (aka glibc or libc6) 2.21 through 2.27 does not correctly perform the overlapping memory check if the source memory range spans the middle of the address space, resulting in corrupt data being produced by the copy operation. This may disclose information to context-dependent attackers, or result in a denial of service, or, possibly, code execution.

Vulnerability class: Buffer Overflow

EPSS: 0.047 (91.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2017-18269?
CVE-2017-18269 is a critical-severity vulnerability in GNU Glibc, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 9.8/10. Published 2018-05-18.
How severe is CVE-2017-18269?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2017-18269 known to be exploited?
4 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.