High severity · published May 7, 2026
CVE-2026-44601
Tor before 0.4.9.7, when circuit queue memory pressure exists, can experience a client crash because of a double close of a circuit, aka TROVE-2026-009
7.5
CVSS
0.3%
EPSS
No
On KEV
Description
Tor before 0.4.9.7, when circuit queue memory pressure exists, can experience a client crash because of a double close of a circuit, aka TROVE-2026-009.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 27% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TO
Tor · torproject
before 0.4.9.7 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-44601
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-44601
Release Notes
https://forum.torproject.org/c/news/tor-release-announcement/28
Patch
https://gitlab.torproject.org/tpo/core/tor/-/commit/d4e3f6a440b58c2be661decf20c09548704907dc
Not Applicable
https://gitlab.torproject.org/tpo/core/tor/-/work_items/41237
Mailing List
https://www.openwall.com/lists/oss-security/2026/05/06/8
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