Apple iOS/iPadOS up to 12.5.1/14.4.1 WebKit cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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5.4$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic has been found in Apple iOS and iPadOS up to 12.5.1/14.4.1. This affects an unknown function of the component WebKit. The manipulation leads to cross site scripting. This vulnerability is referenced as CVE-2021-1879. Remote exploitation of the attack is possible. Furthermore, an exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Apple iOS and iPadOS up to 12.5.1/14.4.1 (Smartphone Operating System) and classified as problematic. This issue affects some unknown processing of the component WebKit. The manipulation with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Impacted is integrity.

The weakness was published 03/26/2021 by Clement Lecigne as HT212256/HT212257 as confirmed advisory (Website). The advisory is shared at support.apple.com. The identification of this vulnerability is CVE-2021-1879. It demands that the victim is doing some kind of user interaction. Technical details are unknown but an exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/29/2025). It is expected to see the exploit prices for this product increasing in the near future.MITRE ATT&CK project uses the attack technique T1059.007 for this issue. The advisory points out:

Processing maliciously crafted web content may lead to universal cross site scripting. Apple is aware of a report that this issue may have been actively exploited.

It is declared as attacked. The CISA Known Exploited Vulnerabilities Catalog lists this issue since 11/03/2021 with a due date of 11/17/2021:

Apply updates per vendor instructions.

Upgrading to version 12.5.2 or 14.4.2 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability. The advisory contains the following remark:

This issue was addressed by improved management of object lifetimes.

The vulnerability is also documented in the databases at Zero-Day.cz (616) and EUVD (EUVD-2021-7343). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.4

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.1
NVD Vector: 🔍

CNA Base Score: 6.1
CNA Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Attacked

EPSS Score: 🔍
EPSS Percentile: 🔍

KEV Added: 🔍
KEV Due: 🔍
KEV Remediation: 🔍
KEV Ransomware: 🔍
KEV Notice: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Zero-Day.cz: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: iOS/iPadOS 12.5.2/14.4.2

Timelineinfo

12/08/2020 🔍
03/26/2021 +108 days 🔍
03/26/2021 +0 days 🔍
03/27/2021 +1 days 🔍
07/29/2025 +1585 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT212256/HT212257
Researcher: Clement Lecigne
Status: Confirmed

CVE: CVE-2021-1879 (🔍)
GCVE (CVE): GCVE-0-2021-1879
GCVE (VulDB): GCVE-100-171905
EUVD: 🔍
scip Labs: https://www.scip.ch/en/?labs.20150917

Entryinfo

Created: 03/27/2021 17:59
Updated: 07/29/2025 06:02
Changes: 03/27/2021 17:59 (18), 03/27/2021 18:02 (29), 04/06/2021 11:30 (5), 04/20/2024 13:33 (26), 05/15/2024 17:15 (2), 06/29/2024 15:00 (2), 09/11/2024 23:15 (1), 01/30/2025 00:15 (28), 05/04/2025 03:00 (3), 07/29/2025 06:02 (1)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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