Medium severity · published Oct 12, 2020
CVE-2020-13943
If an HTTP/2 client connecting to Apache Tomcat 10.0.0-M1 to 10.0.0-M7, 9.0.0.M1 to 9.0.37 or 8.5.0 to 8.5.57 exceeded the agreed maximum number of concurrent streams for a…
4.3
CVSS
55%
EPSS
No
On KEV
Description
If an HTTP/2 client connecting to Apache Tomcat 10.0.0-M1 to 10.0.0-M7, 9.0.0.M1 to 9.0.37 or 8.5.0 to 8.5.57 exceeded the agreed maximum number of concurrent streams for a connection (in violation of the HTTP/2 protocol), it was possible that a subsequent request made on that connection could contain HTTP headers - including HTTP/2 pseudo headers - from a previous request rather than the intended headers. This could lead to users seeing responses for unexpected resources.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
Low
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)55.0% · higher than 99% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TO
Tomcat · Apache
Apache Tomcat 10.0.0-M1 to 10.0.0-M7, 9.0.0.M1 to 9.0.37, 8.5.0 to 8.5.57 · source: vendor, NVD
DL
Debian Linux · Debian
9.0; 10.0 · source: NVD
IE
Instantis Enterprisetrack · Oracle
17.1; 17.2; 17.3 · source: NVD
SE
Sd-wan Edge · Oracle
9.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-13943
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-13943
Mailing List
http://lists.opensuse.org/opensuse-security-announce/2020-11/msg00002.html
Broken Link
http://lists.opensuse.org/opensuse-security-announce/2020-11/msg00021.html
Vendor Advisory
https://lists.apache.org/thread.html/r4a390027eb27e4550142fac6c8317cc684b157ae314d31514747f307%40%3Cannounce.tomcat.apache.org%3E
Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/10/msg00019.html
Third Party Advisory
https://security.netapp.com/advisory/ntap-20201016-0007/
Third Party Advisory
https://www.debian.org/security/2021/dsa-4835
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