CVE-2023-28204Known exploitationNetwork attack vector

Sensitive information disclosure via RegExp position errors

Published Jun 23, 2023 · Updated Oct 21, 2025

An out-of-bounds read in WebKit in Apple operating systems and Safari allows remote attackers to disclose sensitive information through web content. JavaScriptCore's RegExpGlobalData::performMatch mishandles string positions for non-BMP characters during regular-expression assertions and empty matches, reading beyond bounds. Exploitation requires a user to process attacker-controlled web content, and the reported consequence is information disclosure rather than modification or service interruption.

CVSS severity6.5
Medium
EPSS probability14.29%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

An out-of-bounds read in WebKit in Apple operating systems and Safari allows remote attackers to disclose sensitive information through web content. JavaScriptCore's RegExpGlobalData::performMatch mishandles string positions for non-BMP characters during regular-expression assertions and empty matches, reading beyond bounds. Exploitation requires a user to process attacker-controlled web content, and the reported consequence is information disclosure rather than modification or service interruption.

The record

CVE
CVE-2023-28204
Published
Jun 23, 2023
Updated
Oct 21, 2025
Vendor
Apple
Product
iOS and iPadOS
Classifications
CWE-125, T1189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 23, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 21, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <15.7
  2. Affected versionversion=unspecified <16.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Apple · iOS and iPadOSversion=unspecified <15.7; version=unspecified <16.5
Apple · Safariversion=unspecified <16.5
Apple · tvOSversion=unspecified <16.5
Apple · macOSversion=unspecified <13.4
Apple · watchOSversion=unspecified <9.5

Published CVSS scores

6.5CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
6.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationReported
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-125Out-of-bounds Read
T1189Drive-by Compromise

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Reported exploitation

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo