Low severity · published Mar 2, 2022
CVE-2021-3716
A flaw was found in nbdkit due to to improperly caching plaintext state across the STARTTLS encryption boundary
3.1
CVSS
0.6%
EPSS
No
On KEV
Description
A flaw was found in nbdkit due to to improperly caching plaintext state across the STARTTLS encryption boundary. A MitM attacker could use this flaw to inject a plaintext NBD_OPT_STRUCTURED_REPLY before proxying everything else a client sends to the server, potentially leading the client to terminate the NBD session. The highest threat from this vulnerability is to system availability.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 48% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
EL
Enterprise Linux · Redhat
8.0; 8.0 · source: NVD
NB
Nbdkit · Nbdkit Project
1.11.8 before 1.24.6; 1.25.1 before 1.26.5; 1.27.1 before 1.27.6 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-3716
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-3716
Issue Tracking
https://bugzilla.redhat.com/show_bug.cgi?id=1994695
Patch
https://gitlab.com/nbdkit/nbdkit/-/commit/09a13dafb7bb3a38ab52eb5501cba786365ba7fd
Patch
https://gitlab.com/nbdkit/nbdkit/-/commit/6c5faac6a37077cf2366388a80862bb00616d0d8
Broken Link
https://listman.redhat.com/archives/libguestfs/2021-August/msg00083.html
Mailing List
https://www.openwall.com/lists/oss-security/2021/08/18/2
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