CVE-2026-102740

AsyncHttpClient: Resumable download index store is created world-readable and follows a planted symlink

Published Oct 15, 2026 CVSS 3.1 · 5.8 Medium EPSS < 1% KEV · Not listed
Description
The AsyncHttpClient library allows Java applications to execute HTTP requests and asynchronously process HTTP responses. From 2.0.0 until 2.16.1 and 3.0.12, PropertiesBasedResumableProcessor stores resumable download state at the predictable shared path $java.io.tmpdir/ahc/ResumableAsyncHandler.properties with default permissions and link-following file operations. A local user who can read the shared store can see download URLs, including embedded user information or query tokens. A local user who can write within or pre-create the affected shared store directory can plant a symbolic link that the client follows when saving state, truncating and overwriting a target file writable by the client process. The filesystem path is used when ResumableAsyncHandler decorates another AsyncHandler, while the no-argument constructors use a no-op processor and are unaffected. This issue is fixed in versions 2.16.1 and 3.0.12.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Asynchttpclient Project
Asynchttpclient Project async-http-client
Vendors & Products Asynchttpclient Project
Asynchttpclient Project async-http-client
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description The AsyncHttpClient library allows Java applications to execute HTTP requests and asynchronously process HTTP responses. From 2.0.0 until 2.16.1 and 3.0.12, PropertiesBasedResumableProcessor stores resumable download state at the predictable shared path $java.io.tmpdir/ahc/ResumableAsyncHandler.properties with default permissions and link-following file operations. A local user who can read the shared store can see download URLs, including embedded user information or query tokens. A local user who can write within or pre-create the affected shared store directory can plant a symbolic link that the client follows when saving state, truncating and overwriting a target file writable by the client process. The filesystem path is used when ResumableAsyncHandler decorates another AsyncHandler, while the no-argument constructors use a no-op processor and are unaffected. This issue is fixed in versions 2.16.1 and 3.0.12.
Title AsyncHttpClient: Resumable download index store is created world-readable and follows a planted symlink
Weaknesses CWE-379
CWE-61
CWE-732
References
Metrics cvssV3_1

{'score': 5.8, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Oct 15, 2026, 6:27 PM
Reserved
Sep 29, 2026, 4:19 PM
Status
Awaiting Analysis
Published
Oct 15, 2026, 6:17 PM
Modified
Oct 16, 2026, 8:02 PM