Apple Safari up to 15.0 WebKit buffer overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$5k-$25k0.00

Summaryinfo

A vulnerability, which was classified as critical, was found in Apple Safari up to 15.0. Affected by this issue is some unknown functionality of the component WebKit. Executing a manipulation can lead to buffer overflow. This vulnerability is handled as CVE-2021-30934. The attack can be executed remotely. There is not any exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Apple Safari up to 15.0 (Web Browser). This vulnerability affects some unknown functionality of the component WebKit. The manipulation with an unknown input leads to a buffer overflow vulnerability. The CWE definition for the vulnerability is CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was released 12/14/2021 by Dani Biro as HT212982 as confirmed advisory (Website). The advisory is shared for download at support.apple.com. This vulnerability was named CVE-2021-30934. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 03/06/2026). The advisory points out:

Processing maliciously crafted web content may lead to arbitrary code execution

The vulnerability scanner Nessus provides a plugin with the ID 241427 (RHEL 7 : webkitgtk4 (RHSA-2025:10364)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 15.2 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability. The advisory contains the following remark:

A buffer overflow issue was addressed with improved memory handling.

The vulnerability is also documented in the databases at Tenable (241427) and CERT Bund (WID-SEC-2026-0631). Once again VulDB remains the best source for vulnerability data.

Affected

  • Apple macOS

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 241427
Nessus Name: RHEL 7 : webkitgtk4 (RHSA-2025:10364)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: Safari 15.2

Timelineinfo

04/13/2021 🔍
12/14/2021 +245 days 🔍
12/14/2021 +0 days 🔍
12/17/2021 +3 days 🔍
03/06/2026 +1540 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT212982
Researcher: Dani Biro
Status: Confirmed

CVE: CVE-2021-30934 (🔍)
GCVE (CVE): GCVE-0-2021-30934
GCVE (VulDB): GCVE-100-188596
CERT Bund: WID-SEC-2026-0631 - Apple macOS: Mehrere Schwachstellen

Entryinfo

Created: 12/17/2021 16:57
Updated: 03/06/2026 18:51
Changes: 12/17/2021 16:57 (4), 12/17/2021 16:58 (15), 12/17/2021 17:01 (27), 12/23/2021 12:39 (1), 07/10/2025 20:36 (16), 03/06/2026 18:51 (7)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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