High severity · published Feb 21, 2019
CVE-2019-8955
In Tor before 0.3.3.12, 0.3.4.x before 0.3.4.11, 0.3.5.x before 0.3.5.8, and 0.4.x before 0.4.0.2-alpha, remote denial of service against Tor clients and relays can occur via…
7.5
CVSS
4.6%
EPSS
No
On KEV
Description
In Tor before 0.3.3.12, 0.3.4.x before 0.3.4.11, 0.3.5.x before 0.3.5.8, and 0.4.x before 0.4.0.2-alpha, remote denial of service against Tor clients and relays can occur via memory exhaustion in the KIST cell scheduler.
CVSS vector
CVSS:3.0/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)4.6% · higher than 92% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TO
Tor · Torproject
before 0.3.3.12; 0.3.4.8 before 0.3.4.11; 0.3.4.0; 0.3.4.1; 0.3.4.2; 0.3.4.3; +13 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2019-8955
CVE.org
https://www.cve.org/CVERecord?id=CVE-2019-8955
lists.opensuse.org
http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00013.html
Third Party Advisory
http://www.securityfocus.com/bid/107136
Vendor Advisory
https://blog.torproject.org/new-releases-tor-0402-alpha-0358-03411-and-03312
Vendor Advisory
https://trac.torproject.org/projects/tor/ticket/29168
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