Critical severity · published May 7, 2026
CVE-2026-44597
Tor before 0.4.9.7 has an out-of-bounds read when an END, a TRUNCATE, or a TRUNCATED cell lacks a reason in its payload, aka TROVE-2026-011
9.1
CVSS
0.4%
EPSS
No
On KEV
Description
Tor before 0.4.9.7 has an out-of-bounds read when an END, a TRUNCATE, or a TRUNCATED cell lacks a reason in its payload, aka TROVE-2026-011.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 39% 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-2026-44597
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-44597
Release Notes
https://forum.torproject.org/c/news/tor-release-announcement/28
Patch
https://gitlab.torproject.org/tpo/core/tor/-/commit/8f98054b1982d00a14639864d03e9afd90b87481
Broken Link
https://gitlab.torproject.org/tpo/core/tor/-/work_items/41254
Mailing List
https://www.openwall.com/lists/oss-security/2026/05/06/8
More from Tor
7.5
CVE-2016-9079
Mozilla Firefox, Firefox ESR, and Thunderbird Use-After-Free Vulnerability
9.3
CVE-2026-77642
tor before 0.4.9.9 was prone to an out-of-bounds write when parsing a consensus or detached signature with unexpected signature digest type
9.1
CVE-2026-44603
Tor before 0.4.9.7 has an out-of-bounds read by one byte via a malformed BEGIN cell, aka TROVE-2026-007
9.0
CVE-2026-77638
Tor before 0.4.9.11 is prone to a race condition where in just the right circumstances a rendezvous point could man-in-the-middle (impersonate) the onion service that the client…
8.2
CVE-2026-77641
tor before 0.4.9.9 was prone to a NULL write after free when sending a CONFLUX_SWITCH cell fails