Uncaught Exception Affecting aiohttp package, versions [,3.14.4)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published20 Oct 2026
- disclosed6 Oct 2026
- creditDenys Pakizh
Introduced: 6 Oct 2026
NewCVE-2026-111065 (opens in a new tab)How to fix?
Upgrade aiohttp to version 3.14.4 or higher.
Overview
Affected versions of this package are vulnerable to Uncaught Exception in the update_cookies method of CookieJar in aiohttp/cookiejar.py, which computes time.time() + delta_seconds from the Max-Age attribute while catching only ValueError, so a sufficiently large value raises out of cookie processing. An attacker running the server can hold client connections out of the pool, up to temporary exhaustion, by returning a Set-Cookie header with such a Max-Age, because the exception is raised after the response has been received and _request does not close the ClientResponse on that failure path, leaving the connection unreleased. This requires the client to make requests to a server the attacker controls or has compromised with cookie processing in use, and the effect is temporary, since garbage collection eventually reclaims the connections.