Use After Free Affecting tor package, versions <0.3.1.9-1
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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Test your applications- Snyk IDSNYK-ECHOLATEST-TOR-19166185
- published22 Aug 2026
- disclosed3 Dec 2017
Introduced: 3 Dec 2017
CVE-2017-8823 (opens in a new tab)How to fix?
Upgrade Echo:latest tor to version 0.3.1.9-1 or higher.
NVD Description
Note: Versions mentioned in the description apply only to the upstream tor package and not the tor package as distributed by Echo.
See How to fix? for Echo:latest relevant fixed versions and status.
In Tor before 0.2.5.16, 0.2.6 through 0.2.8 before 0.2.8.17, 0.2.9 before 0.2.9.14, 0.3.0 before 0.3.0.13, and 0.3.1 before 0.3.1.9, there is a use-after-free in onion service v2 during intro-point expiration because the expiring list is mismanaged in certain error cases, aka TROVE-2017-013.