High severity · published Jun 29, 2021
CVE-2021-34548
An issue was discovered in Tor before 0.4.6.5, aka TROVE-2021-003
7.5
CVSS
2.6%
EPSS
No
On KEV
Description
An issue was discovered in Tor before 0.4.6.5, aka TROVE-2021-003. An attacker can forge RELAY_END or RELAY_RESOLVED to bypass the intended access control for ending a stream.
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)2.6% · higher than 85% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TO
Tor · Torproject
before 0.3.5.15; 0.4.0.0 before 0.4.4.9; 0.4.5.0 before 0.4.5.9; 0.4.6.0 before 0.4.6.5 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-34548
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-34548
Third Party Advisory
http://packetstormsecurity.com/files/163510/Tor-Half-Closed-Connection-Stream-Confusion.html
Release Notes
https://blog.torproject.org/node/2041
Broken Link
https://gitlab.torproject.org/tpo/core/tor/-/issues/40389
Third Party Advisory
https://security.gentoo.org/glsa/202107-25
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