Every CVE Search/ Get API key

CVE-2021-3420

A flaw was found in newlib in versions prior to 4.0.0. Improper overflow validation in the memory...

9.8 CriticalFix available

A flaw was found in newlib in versions prior to 4.0.0. Improper overflow validation in the memory allocation functions mEMALIGn, pvALLOc, nano_memalign, nano_valloc, nano_pvalloc could case an integer overflow, leading to an allocation of a small buffer and then to a heap-based buffer overflow.

Attack profile

How easy it is to exploit

Attack vector
Network
Complexity
Low
Privileges needed
None
User interaction
None

What an attacker can affect

Confidentiality
High
Integrity
High
Availability
High

Exploit likelihood

2.10%Up 1.1 points since Apr 14, 2021
90%50%10%1%

What each source reports

NVD Score used 9.8

A flaw was found in newlib in versions prior to 4.0.0. Improper overflow validation in the memory allocation functions mEMALIGn, pvALLOc, nano_memalign, nano_valloc, nano_pvalloc could case an integer overflow, leading to an allocation of a small buffer and then to a heap-based buffer overflow.

Record
CVE-2021-3420
CVSS 3.1
9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS 2.0
7.5 HighAV:N/AC:L/Au:N/C:P/I:P/A:P
Weakness
CWE-190
Updated
2026-11-02
CVE List No score

A flaw was found in newlib in versions prior to 4.0.0. Improper overflow validation in the memory allocation functions mEMALIGn, pvALLOc, nano_memalign, nano_valloc, nano_pvalloc could case an integer overflow, leading to an allocation of a small buffer and then to a heap-based buffer overflow.

Record
CVE-2021-3420
Weakness
CWE-190
Updated
2026-11-02
EUVDEUVD-2021-26748 No score

A flaw was found in newlib in versions prior to 4.0.0. Improper overflow validation in the memory allocation functions mEMALIGn, pvALLOc, nano_memalign, nano_valloc, nano_pvalloc could case an integer overflow, leading to an allocation of a small buffer and then to a heap-based buffer overflow.

Record
EUVD-2021-26748
Updated
2026-11-03
GitHub AdvisoriesGHSA-wp32-4vw5-mw9c No score

A flaw was found in newlib in versions prior to 4.0.0. Improper overflow validation in the memory...

A flaw was found in newlib in versions prior to 4.0.0. Improper overflow validation in the memory allocation functions mEMALIGn, pvALLOc, nano_memalign, nano_valloc, nano_pvalloc could case an integer overflow, leading to an allocation of a small buffer and then to a heap-based buffer overflow.

Record
GHSA-wp32-4vw5-mw9c
Weakness
CWE-120
Updated
2026-11-02
OSVALPINE-CVE-2021-3420 9.8

A flaw was found in newlib in versions prior to 4.0.0. Improper overflow validation in the memory allocation functions mEMALIGn, pvALLOc, nano_memalign, nano_valloc, nano_pvalloc could case an integer overflow, leading to an allocation of a small buffer and then to a heap-based buffer overflow.

Record
ALPINE-CVE-2021-3420
CVSS 3.1
9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Updated
2026-11-03
OSV 9.8

A flaw was found in newlib in versions prior to 4.0.0. Improper overflow validation in the memory allocation functions mEMALIGn, pvALLOc, nano_memalign, nano_valloc, nano_pvalloc could case an integer overflow, leading to an allocation of a small buffer and then to a heap-based buffer overflow.

Record
CVE-2021-3420
CVSS 3.1
9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Updated
2026-11-02
OSVDEBIAN-CVE-2021-3420 9.8

A flaw was found in newlib in versions prior to 4.0.0. Improper overflow validation in the memory allocation functions mEMALIGn, pvALLOc, nano_memalign, nano_valloc, nano_pvalloc could case an integer overflow, leading to an allocation of a small buffer and then to a heap-based buffer overflow.

Record
DEBIAN-CVE-2021-3420
CVSS 3.1
9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Updated
2026-11-02
OSVUBUNTU-CVE-2021-3420 9.8

A flaw was found in newlib in versions prior to 4.0.0. Improper overflow validation in the memory allocation functions mEMALIGn, pvALLOc, nano_memalign, nano_valloc, nano_pvalloc could case an integer overflow, leading to an allocation of a small buffer and then to a heap-based buffer overflow.

Record
UBUNTU-CVE-2021-3420
CVSS 3.1
9.8 CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Updated
2026-11-02
OSVopenSUSE-SU-2024:11086-1 No score

newlib-4.1.0-2.2 on GA media

These are all security issues fixed in the newlib-4.1.0-2.2 package on the GA media of openSUSE Tumbleweed.

Record
openSUSE-SU-2024:11086-1
Updated
2026-11-02

Affected products

Affected packages

Affected packages
PackageAffectedFixed
newlib
Alpine:v3.14
before 4.1.0-r0
4.1.0-r0
newlib
Alpine:v3.15
before 4.1.0-r0
4.1.0-r0
newlib
Alpine:v3.16
before 4.1.0-r0
4.1.0-r0
newlib
Alpine:v3.17
before 4.1.0-r0
4.1.0-r0
newlib
Alpine:v3.18
before 4.1.0-r0
4.1.0-r0
newlib
Alpine:v3.19
before 4.1.0-r0
4.1.0-r0
newlib
Alpine:v3.20
before 4.1.0-r0
4.1.0-r0
newlib
Alpine:v3.21
before 4.1.0-r0
4.1.0-r0
newlib
Alpine:v3.22
before 4.1.0-r0
4.1.0-r0
newlib
Alpine:v3.23
before 4.1.0-r0
4.1.0-r0
Show 13 moreShow less
Affected packages
PackageAffectedFixed
newlib
Alpine:v3.24
before 4.1.0-r0
4.1.0-r0
newlib
Debian:12
before 3.3.0-1.3+deb12u1, plus listed versions
3.3.0-1.3
3.3.0-1.3+deb12u1
newlib
Debian:13
before 4.4.0.20231231-2
4.4.0.20231231-2
newlib
Debian:14
before 4.4.0.20231231-2
4.4.0.20231231-2
picolibc
Debian:12
before 1.5-1
1.5-1
picolibc
Debian:13
before 1.5-1
1.5-1
picolibc
Debian:14
before 1.5-1
1.5-1
newlib
Ubuntu:16.04:LTS
All versions, plus listed versions
2.1.0+git20141201.db59ff3-22.2.0+git20150830.5a3d536-1
None known
newlib
Ubuntu:18.04:LTS
All versions, plus listed versions
2.4.0.20160527-22.4.0.20160527-32.4.0.20160527-3ubuntu0.1
None known
newlib
Ubuntu:20.04:LTS
All versions, plus listed versions
3.1.0.20181231-13.3.0-0ubuntu1
None known
newlib
Ubuntu:22.04:LTS
All versions, plus listed versions
3.3.0-13.3.0-1.23.3.0-1.3
None known
newlib
Ubuntu:24.04:LTS
All versions, plus listed versions
3.3.0-1.34.4.0.20231231-2
None known
newlib
openSUSE:Tumbleweed
before 4.1.0-2.2
4.1.0-2.2

History

History
RecordedChangedSources
affected, aliases, referencesOSV
aliases, productsEUVD
first indexedCVE List, GitHub Advisories, NVD, OSV

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2021-3420 is a critical vulnerability (CVSS 9.8) in Newlib Project Newlib, published March 5, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.10%, the 81st percentile. Fixed in newlib 4.1.0-r0.

References

Show 9 moreShow less
MoveEnter Open