Background exploitation KEV catalog No authentication

CVE-2021-31010

Apple iOS, macOS, watchOS Sandbox Bypass Vulnerability

CheckOps priority index

4.9/10 Patch within 7 days

Severity7.5

Probability0.4

Exploitation3/5

Severity = CVSS. Probability = EPSS (FIRST). Exploitation = public signals: KEV, EUVD, ransomware, EPSS above 10 %, no account required.

EPSS · today 3.7% higher than 89.7% of CVEs

CVSS 3.1 7.5 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:

Exploited for 1,531 days 25 Aug 2022

CISA due date 15 Sept 2022 for US federal agencies

Exploitation probability EPSS · FIRST

EPSS probability (%)Percentile among all CVEs

Exploitation signals 3 / 5

KEV catalog (CISA)25 Aug 2022
Exploited in EUVD (ENISA)25 Aug 2022
Used by ransomwareno
EPSS above 10 %3.7%
No account, over the networkyes

What to do

Fix

Apply the vendor’s fix as soon as it is available.

CISA guidance: Apply updates per vendor instructions.

Meanwhile

Take the service off the internet or restrict access to it, watch the logs and look for signs of compromise.

Manufacturers (CRA)

Exploited vulnerability in your product: early warning to ENISA within 24 h, then notification within 72 h (Article 14 of the Cyber Resilience Act). The CRA explained

Description ENISA EUVD

A deserialization issue was addressed through improved validation. This issue is fixed in Security Update 2021-005 Catalina, iOS 12.5.5, iOS 14.8 and iPadOS 14.8, macOS Big Sur 11.6, watchOS 7.6.2. A sandboxed process may be able to circumvent sandbox restrictions. Apple was aware of a report that this issue may have been actively exploited at the time of release..

Affected products

macOSwatchOSiOS, macOS, watchOS

Affected versions

unspecified <11.6
unspecified <14.8
unspecified <12.5
unspecified <7.6
unspecified <2021

Weaknesses (CWE)

CWE-20 CWE-502

Open source packages OSV

Affected libraries according to OSV, with fixed versions.

Timeline

24 Aug 2021
Published
25 Aug 2022
Exploitation reported (ENISA)
25 Aug 2022
Added to the KEV catalog
15 Sept 2022
CISA remediation due date

References

Other exploited vulnerabilities from the same vendor

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CVE-2026-65400Apple macOS Improper Authentication Vulnerability
5.8 · Actively exploited
CVE-2025-43520Apple Multiple Products Classic Buffer Overflow Vulnerability
3.4 · Background exploitation
CVE-2025-43510Apple Multiple Products Improper Locking Vulnerability
4.3 · Background exploitation
CVE-2025-31277Apple Multiple Products Buffer Overflow Vulnerability
5.4 · Background exploitation
CVE-2023-43000Apple Multiple products Use-After-Free Vulnerability
5.4 · Background exploitation