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NVD / CVE Program· CNA apple

CVE-2021-30761: A memory corruption issue was addressed with improved state management.

HighCVSS 8.8 · v3.1KEVWeaponized Fix available

Noroxi assessment

Priority: This week (action score 68/100)

  • CISA has confirmed exploitation in the wild (Nov 3, 2021). Remediation deadline for US federal agencies: Nov 17, 2021.
  • Probability of exploitation in the next 30 days: 10.5% (FIRST EPSS); higher than 95.8% of all records.
  • Anyone who can reach it over the internet can trigger it. No account or password is required. A user must open a link or visit a page. No special conditions are required; it is repeatable.
  • Fixed version: webkit2gtk (Alpine:v3.14) 2.26.0-r0; webkit2gtk (Debian:10) 2.26.1-3~deb10u1; webkit2gtk (Debian:12) 2.26.1-2.
  • Mentioned 2 times in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Don’t wait for the next maintenance window. Upgrade to webkit2gtk (Alpine:v3.14) 2.26.0-r0; webkit2gtk (Debian:10) 2.26.1-3~deb10u1; webkit2gtk (Debian:12) 2.26.1-2 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · CISA KEV · FIRST EPSS

A memory corruption issue was addressed with improved state management. This issue is fixed in iOS 12.5.4. Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited..

Published
Sep 8, 2021
Updated
Jun 16, 2026
EPSS
10.5% · 95th percentile

Report tools

JSON

Action score

68

This week

Don’t wait for the next maintenance window.

CVSS
35 / 40 · 8.8 / 10
CISA KEV
30 / 30 · Listed
EPSS
3 / 30 · 10.5%

CISA SSVC decision

Exploitation
active
Automatable
no
Technical impact
total

Vulnrichment: CISA's decision-tree inputs.

Actively exploited in the wild

CISA added this to its Known Exploited Vulnerabilities catalog on Nov 3, 2021. That signals real attacks, not theory.

Remediation deadline for US federal agencies: Nov 17, 2021.

Get told when this record changes

  • In CISA KEV: exploitation in the wild confirmed
  • Weaponized exploit exists
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2021-30761

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
appleiphone os

Versions reported by the vendor

Affected version ranges reported by the assigning authority (apple). Independent of NVD's CPE analysis and usually ahead of it.

  • Apple iOS

    • unspecified and later · before 12.5affected

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • apple iphone osbefore 12.5.4

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Alpine:v3.14webkit2gtkbefore 2.26.0-r02.26.0-r0
Debian:10webkit2gtkbefore 2.26.1-3~deb10u12.26.1-3~deb10u1
Debian:12webkit2gtkbefore 2.26.1-22.26.1-2
Debian:12wpewebkitbefore 2.26.3-12.26.3-1

Same product

apple: all records

Other highest-scoring records for the same primary product.

  • CVE-2016-4657WebKit in Apple iOS before 9.3.5 allows remote attackers to execute arbitrary code or cause a denial of service (memory corruption) via a…KEV
    85Now
  • CVE-2014-4404Heap-based buffer overflow in IOHIDFamily in Apple iOS before 8 and Apple TV before 7 allows attackers to execute arbitrary code in a…KEV
    76This week
  • CVE-2021-30762A use after free issue was addressed with improved memory management.KEV
    68This week

Published before and after this one in the same product

  • ← EarlierCVE-2021-30871Aug 24, 2021 · This issue was addressed with a new entitlement.
    22Monitor
  • ← EarlierCVE-2021-30968Aug 24, 2021 · A validation issue related to hard link behavior was addressed with improved sandbox restrictions.
    22Monitor
  • Later →CVE-2021-30768Sep 8, 2021 · A logic issue was addressed with improved validation.
    22Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
alpine:webkit2gtk2.26.0-r0 · Alpine:v3.14Package registry (OSV)
debian:webkit2gtk2.26.1-2 · Debian:12Package registry (OSV)
debian:wpewebkit2.26.3-1 · Debian:12Package registry (OSV)

Exploit status

Weaponized

A ready exploit tool or active in-the-wild use is known for this vulnerability. This should be your top priority.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. Published
  2. CISA KEV+56 d
  3. TodayNov 14, 2026+1893 d

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Not on record for this CVE: EPSS history · patch commit or PR link · researcher credit · variant or chain candidate · public bounty program.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • A user must open a link or visit a page.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
high · data or configuration can be modified
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
Required
Scope
Unchanged
Confidentiality impact
High
Integrity impact
High
Availability impact
High

Weakness class (CWE)

CWE-787 · Out-of-bounds Write

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

nvd-primary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

References

Show all references (1 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records