CVE-2021-30952
Exploitation confirmed. First attested on 2026-03-05 by CISA-ADP, CISA KEV, GCVE · kevintel.
- Published2021-08-24
- WeaknessCWE-190
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
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.
Timeline
dates in UTCObserved activity
isMalicious corpus · updated 2026-10-23 18:48 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-30952?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-30952?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 10.0 | = 10.0 | no fix published | NVD |
| 11.0 | = 11.0 | no fix published | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 34.x | = 34 | no fix published | NVD |
| 35.x | = 35 | no fix published | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 15.2 | < 15.2 | 15.2 | NVD |
7 more products in the sources.
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
- CISA’s 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.due 2026-03-26
Advisories and patches
- support.apple.comRelease Notes · Vendor Advisory
- support.apple.comRelease Notes · Vendor Advisory
- support.apple.comRelease Notes · Vendor Advisory
- support.apple.comRelease Notes · Vendor Advisory
- support.apple.comRelease Notes · Vendor Advisory
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
CISA Known Exploited Vulnerability
- Date Added
- 2026-03-05
- Patch Due Date
- 2026-03-26
- Ransomware Use
- Unknown
- 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.
Sources
- CISA KEVKEV entry2026-03-05
- GCVEexploitation2026-03-05
- CISA-ADPSSVC decisionactive2026-03-05
- OpenCVESSVC decisionactive—
- CISA-ADPCVSS 3.18.82026-03-05
- NVDCVSS 3.17.8read 2026-10-23
- NVDCVSS 2.06.8read 2026-10-23
- CISA-ADPweakness (CWE)CWE-1902026-03-05
- NVDweakness (CWE)CWE-190read 2026-10-23
- FIRST EPSSEPSS score7.0 %2026-10-22
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- Published
- 2021-08-24
- Last Modified
- 2026-06-17
- NVD status
- Analyzed
Frequently asked questions
What is CVE-2021-30952?
Is CVE-2021-30952 actively exploited?
What is the CVSS score for CVE-2021-30952?
Hear about the next vulnerability in your software
Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».
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Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.