CVE-2021-30952

Exp

An integer overflow was addressed with improved input validation. This issue is fixed in tvOS 15.2, macOS Monterey 12.1, Safari 15.2, iOS 15.2 and iPadOS 15.2, watchOS 8.3. Processing maliciously crafted web content may lead to arbitrary code execution.

Published: 2021-08-24 Last update: 2026-03-06 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-30952 is rated Critical Active Threat (82/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.79%). CISA KEV confirms active exploitation (added 2026-03-05) affecting Apple / Multiple Products. a weakness (CWE-190) Unauthenticated remote administrative access may be possible. The CISA remediation deadline has passed—treat as an emergency patch priority.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

CISA KEV Record for CVE-2021-30952

Name: Apple Multiple Products Integer Overflow or Wraparound Vulnerability · CISA KEV detail

Exploit added: 2026-03-05

Action due: 2026-03-26

Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Public exploit references (Exploit-DB) for CVE-2021-30952

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-30952

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-30 0.91% 0.79% -0.12%
2 2026-05-29 0.78% 0.91% +0.13%
3 2026-05-28 — 0.78% —

Full EPSS history (33 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-30952

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.8 3.1 HIGH
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 5.9 [email protected]
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 5.9 134c704f-9b21-4f2e-91b3-4a467353bcc0
6.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.6 6.4 [email protected]

Weakness enumeration for CVE-2021-30952

OS Trackers for CVE-2021-30952

vendor priority summary link
alpine — CVE-2021-30952: 1 source package rows (webkit2gtk); 5 state rows across 5 repos (3.17-community, 3.18-community, 3.19-community, 3.20-community, edge-community); fixed 5, open 0. https://security.alpinelinux.org/vuln/CVE-2021-30952
debian not yet assigned CVE-2021-30952 not yet assigned priority: Debian including 2 source packages (webkit2gtk, wpewebkit), 10 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 10. https://security-tracker.debian.org/tracker/CVE-2021-30952
gentoo high CVE-2021-30952: 1 GLSA(s) (202202-01), 1 atom(s) (net-libs/webkit-gtk); latest impact high. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2021-30952
redhat medium — https://access.redhat.com/security/cve/CVE-2021-30952
suse high CVE-2021-30952 severity important: SUSE including 139 source package names (WebKit2GTK-4.1-lang-2.36.0-150400.2.13, WebKit2GTK-5.0-lang-2.36.0-150400.2.12, …), 429 product×package rows across 60 product lines (HPE Helion OpenStack 8, SUSE CaaS Platform 4.0, … (60 product lines)): Fixed 427, Known Not Affected 2. https://www.suse.com/security/cve/CVE-2021-30952/
ubuntu medium CVE-2021-30952 medium priority: Ubuntu including 5 source packages (qtwebkit-opensource-src, qtwebkit-source, webkit2gtk, webkitgtk, wpewebkit), 55 status rows across 11 suites (bionic, focal, impish, jammy, kinetic, lunar, mantic, noble, trusty, upstream, xenial): DNE 25, ignored 19, released 8, needs-triage 3. https://ubuntu.com/security/CVE-2021-30952

Affected software / configurations for CVE-2021-30952

Vendor Product Version Raw CPE
apple safari < 15.2 cpe:2.3:a:apple:safari:*:*:*:*:*:*:*:*
apple ipados < 15.2 cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:*
apple iphone_os < 15.2 cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
apple macos >= 12.0, < 12.1 cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:*
apple tvos < 15.2 cpe:2.3:o:apple:tvos:*:*:*:*:*:*:*:*
apple watchos < 8.3 cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*
fedoraproject fedora 34 cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
fedoraproject fedora 35 cpe:2.3:o:fedoraproject:fedora:35:*:*:*:*:*:*:*
debian debian_linux 10.0 cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
debian debian_linux 11.0 cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*
webkitgtk webkitgtk < 2.34.4 cpe:2.3:a:webkitgtk:webkitgtk:*:*:*:*:*:*:*:*
wpewebkit wpe_webkit < 2.34.4 cpe:2.3:a:wpewebkit:wpe_webkit:*:*:*:*:*:*:*:*

References for CVE-2021-30952

URL Tags
http://www.openwall.com/lists/oss-security/2022/01/21/2 Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7EQVZ3CEMTINLBZ7PBC7WRXVEVCRHNSM/ Broken Link
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HQKWD4BXRDD2YGR5AVU7H5J5PIQIEU6V/ Broken Link
https://support.apple.com/en-us/HT212975 Release Notes Vendor Advisory
https://support.apple.com/en-us/HT212976 Release Notes Vendor Advisory
https://support.apple.com/en-us/HT212978 Release Notes Vendor Advisory
https://support.apple.com/en-us/HT212980 Release Notes Vendor Advisory
https://support.apple.com/en-us/HT212982 Release Notes Vendor Advisory
https://www.debian.org/security/2022/dsa-5060 Mailing List Third Party Advisory
https://www.debian.org/security/2022/dsa-5061 Mailing List Third Party Advisory
https://cloud.google.com/blog/topics/threat-intelligence/coruna-powerful-ios-exploit-kit Exploit Third Party Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30952 US Government Resource
cvelogic Threat Intelligence