CVE-2021-37973
Exploited in the Wild
✓ Confirmed 0-Day
★ Google Project Zero
Triaged: March 5, 2026
11 articles
EPSS Score
Source: FIRST.org · 2026-05-24
14.78%
probability
This CVE has a 14.78% probability
of being exploited in the next 30 days.
0%
Top 94.6th percentile of all CVEs
100%
CVSS score unavailable
Neither CIRCL nor NVD returned a CVSS score for this CVE.
View on VulnerabilityLookup ↗
Description
Project ZeroUse-after-free in Portals
Attack Intelligence
CWE-118
· Incorrect Access of Indexable Resource ('Range Error')
CWE-119
· Buffer Overflow
CWE-416
· Use After Free
CWE-664
· Improper Control of a Resource Through its Lifetime
CWE-666
· Operation on Resource in Wrong Phase of Lifetime
CWE-672
· Operation on a Resource after Expiration or Release
CWE-825
· Expired Pointer Dereference
Google Project Zero
Discovered
Sept. 21, 2021
Patched
Sept. 24, 2021
Reported by
Clément Lecigne from Google TAG, with technical assistance from Sergei Glazunov and Mark Brand from Google Project Zero
Root Cause Analysis
???
Google pushes emergency Chrome update to fix zero-day used in attacks
BleepingComputer
Dec 13, 2021
Emergency Google Chrome update fixes zero-days used in attacks
BleepingComputer
Oct 28, 2021
Google pushes emergency Chrome update to fix two zero-days
BleepingComputer
Sep 30, 2021
Google Chrome emergency update fixes zero-day exploited in attacks
BleepingComputer
Feb 14, 2022
Emergency Google Chrome update fixes zero-day exploited in the wild
BleepingComputer
Sep 24, 2021
Google: Predator spyware infected Android devices using zero-days
BleepingComputer
May 22, 2022
Qualys Response to CISA Alert: Binding Operational Directive 22-01
Qualys
Nov 09, 2021
Signal Intelligence
Confidence
95%
EPSS
14.78%
Mentions
11
Last Seen
May 22, 2022
CNA Information
Analyst Note
Auto-imported from Google Project Zero — confirmed zero-day by definition.
Threat Actors 6
Turla Group
apt_group
Information theft and espionage
Russian Federation
APT 29
apt_group
Information theft and espionage
🇷🇺 RU
APT 28
apt_group
Information theft and espionage
🇷🇺 RU
Pat Bear
apt_group
🇸🇾 SY
PassCV
apt_group
Information theft and espionage
🇨🇳 CN
APT 5
apt_group
Information theft and espionage
🇨🇳 CN
Triage Info
Decided atMar 05, 2026