High severity · published Aug 20, 2026
CVE-2026-77587
Tor before 0.4.9.11 is prone to a use-after-free (and potential double free) of a conflux object when a recovery leg revives a conflux set whose last linked leg has already been…
7.5
CVSS
0.4%
EPSS
No
On KEV
Description
Tor before 0.4.9.11 is prone to a use-after-free (and potential double free) of a conflux object when a recovery leg revives a conflux set whose last linked leg has already been closed. A malicious exit node could use this to crash a client. This is TROVE-2026-026.
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)0.4% · higher than 35% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TO
Tor · torproject
0.4.8.1-alpha before 0.4.9.11 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-77587
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-77587
Permissions Required
https://gitlab.torproject.org/tpo/core/tor/-/raw/tor-0.4.9.11/ChangeLog
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