0.0
NA
CVE-2025-34091
Google Chrome AppBound Encryption Padding Oracle
Description

Rejected reason: Neither filed by Chrome nor a valid security vulnerability.

INFO

Published Date :

July 2, 2025, 8:15 p.m.

Last Modified :

July 24, 2025, 7:15 a.m.

Source :

[email protected]

Remotely Exploitable :

No

Impact Score :

Exploitability Score :

Affected Products

The following products are affected by CVE-2025-34091 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Google chrome
: Total Affected Vendor : 1 | Products : 1

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2025-34091 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2025-34091 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Rejected by [email protected]

    Jul. 24, 2025

    Action Type Old Value New Value
  • CVE Modified by [email protected]

    Jul. 24, 2025

    Action Type Old Value New Value
    Changed Description A padding oracle vulnerability exists in Google Chrome’s AppBound cookie encryption mechanism due to observable decryption failure behavior in Windows Event Logs when handling malformed ciphertext in SYSTEM-DPAPI-encrypted blobs. A local attacker can repeatedly send malformed ciphertexts to the Chrome elevation service and distinguish between padding and MAC errors, enabling a padding oracle attack. This allows partial decryption of the SYSTEM-DPAPI layer and eventual recovery of the user-DPAPI encrypted cookie key, which is trivially decrypted by the attacker’s own context. This issue undermines the core purpose of AppBound Encryption by enabling low-privileged cookie theft through cryptographic misuse and verbose error feedback. Confirmed in Google Chrome with AppBound Encryption enabled. Other Chromium-based browsers may be affected if they implement similar COM-based encryption mechanisms. This behavior arises from a combination of Chrome’s AppBound implementation and the way Microsoft Windows DPAPI reports decryption failures via Event Logs. As such, the vulnerability relies on cryptographic behavior and error visibility in all supported versions of Windows. Rejected reason: Neither filed by Chrome nor a valid security vulnerability.
    Removed CVSS V4.0 VulnCheck: AV:L/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Removed CWE VulnCheck: CWE-203
    Removed CWE VulnCheck: CWE-209
    Removed Reference VulnCheck: https://vulncheck.com/advisories/google-chrome-appbound-cookie-encryption
    Removed Reference VulnCheck: https://www.cyberark.com/resources/threat-research-blog/c4-bomb-blowing-up-chromes-appbound-cookie-encryption
  • New CVE Received by [email protected]

    Jul. 02, 2025

    Action Type Old Value New Value
    Added Description A padding oracle vulnerability exists in Google Chrome’s AppBound cookie encryption mechanism due to observable decryption failure behavior in Windows Event Logs when handling malformed ciphertext in SYSTEM-DPAPI-encrypted blobs. A local attacker can repeatedly send malformed ciphertexts to the Chrome elevation service and distinguish between padding and MAC errors, enabling a padding oracle attack. This allows partial decryption of the SYSTEM-DPAPI layer and eventual recovery of the user-DPAPI encrypted cookie key, which is trivially decrypted by the attacker’s own context. This issue undermines the core purpose of AppBound Encryption by enabling low-privileged cookie theft through cryptographic misuse and verbose error feedback. Confirmed in Google Chrome with AppBound Encryption enabled. Other Chromium-based browsers may be affected if they implement similar COM-based encryption mechanisms. This behavior arises from a combination of Chrome’s AppBound implementation and the way Microsoft Windows DPAPI reports decryption failures via Event Logs. As such, the vulnerability relies on cryptographic behavior and error visibility in all supported versions of Windows.
    Added CVSS V4.0 AV:L/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CWE CWE-203
    Added CWE CWE-209
    Added Reference https://vulncheck.com/advisories/google-chrome-appbound-cookie-encryption
    Added Reference https://www.cyberark.com/resources/threat-research-blog/c4-bomb-blowing-up-chromes-appbound-cookie-encryption
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2025-34091 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2025-34091 weaknesses.

NONE - Vulnerability Scoring System
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