CVE-2026-76151: CWE-125 Out-of-bounds Read in qt
CVE-2026-76151 is an out-of-bounds read vulnerability in the HTTP Cache-Control response header parsing within the QtNetwork module of Qt versions 6.0.0 through 6.8.8 and 6.9.0 through 6.11.1. This flaw allows remote attackers to cause a denial of service (application crash) by sending an excessively large Cache-Control header value from an untrusted or compromised HTTP server to a client application using QNetworkAccessManager. The issue affects only the client side, does not impact 32-bit builds, and involves read-only out-of-bounds access without information disclosure or code execution.
AI Analysis
Technical Summary
An out-of-bounds read (buffer over-read) vulnerability exists in the HTTP Cache-Control response header parsing in the QtNetwork module of Qt versions >=6.0.0 <6.8.9 and >=6.9.0 <6.11.2. Remote attackers can trigger a denial of service by providing an excessively large Cache-Control header value to applications using QNetworkAccessManager. The vulnerability affects only 64-bit client-side builds, involves read-only access, and does not lead to information disclosure or code execution.
Potential Impact
The vulnerability allows remote attackers to cause a denial of service via application crash on the client side when processing a maliciously large Cache-Control header. There is no impact on information confidentiality or integrity, and no code execution is possible. 32-bit builds are not affected.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, avoid connecting to untrusted or potentially compromised HTTP servers. Monitor vendor communications for patches addressing this vulnerability.
CVE-2026-76151: CWE-125 Out-of-bounds Read in qt
Description
CVE-2026-76151 is an out-of-bounds read vulnerability in the HTTP Cache-Control response header parsing within the QtNetwork module of Qt versions 6.0.0 through 6.8.8 and 6.9.0 through 6.11.1. This flaw allows remote attackers to cause a denial of service (application crash) by sending an excessively large Cache-Control header value from an untrusted or compromised HTTP server to a client application using QNetworkAccessManager. The issue affects only the client side, does not impact 32-bit builds, and involves read-only out-of-bounds access without information disclosure or code execution.
CVSS v4.0
Score 4.6medium
Affected software
qt
qt
pkg:maven/org.qtproject/qtRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
An out-of-bounds read (buffer over-read) vulnerability exists in the HTTP Cache-Control response header parsing in the QtNetwork module of Qt versions >=6.0.0 <6.8.9 and >=6.9.0 <6.11.2. Remote attackers can trigger a denial of service by providing an excessively large Cache-Control header value to applications using QNetworkAccessManager. The vulnerability affects only 64-bit client-side builds, involves read-only access, and does not lead to information disclosure or code execution.
Potential Impact
The vulnerability allows remote attackers to cause a denial of service via application crash on the client side when processing a maliciously large Cache-Control header. There is no impact on information confidentiality or integrity, and no code execution is possible. 32-bit builds are not affected.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, avoid connecting to untrusted or potentially compromised HTTP servers. Monitor vendor communications for patches addressing this vulnerability.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Qt
- Date Reserved
- 2026-08-19T06:21:50.153Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6aaa6ccc55bf5e2cf558c5ce
Added to database: 09/16/2026, 10:17:48 UTC
Last enriched: 09/16/2026, 10:31:40 UTC
Last updated: 09/16/2026, 10:33:32 UTC
Views: 4
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