Login Request a demo
High severity · published Dec 3, 2020
CVE-2020-17527
Apache Tomcat: Request header mix-up between HTTP/2 streams
7.5
CVSS
24.6%
EPSS
No
On KEV
Description
While investigating bug 64830 it was discovered that Apache Tomcat 10.0.0-M1 to 10.0.0-M9, 9.0.0-M1 to 9.0.39 and 8.5.0 to 8.5.59 could re-use an HTTP request header value from the previous stream received on an HTTP/2 connection for the request associated with the subsequent stream. While this would most likely lead to an error and the closure of the HTTP/2 connection, it is possible that information could leak between requests.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)24.6% · higher than 98% 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 10.0.0-M1 to 10.0.0-M9; Apache Tomcat 9 9.0.0-M1 to 9.0.39; Apache Tomcat 8.5 8.5.0 to 8.5.59 · source: vendor, NVD
BP
Blockchain Platform · Oracle
before 21.1.2 · source: NVD
CC
Communications Cloud Native Core Binding Support Function · Oracle
1.10.0 · source: NVD
CC
Communications Cloud Native Core Policy · Oracle
1.14.0 · source: NVD
CI
Communications Instant Messaging Server · Oracle
10.0.1.5.0 · source: NVD
DL
Debian Linux · Debian
9.0; 10.0 · source: NVD
EP
Element Plug-in · Netapp
All versions, or not specified · source: NVD
IE
Instantis Enterprisetrack · Oracle
17.1; 17.2; 17.3 · source: NVD
ME
Mysql Enterprise Monitor · Oracle
before 8.0.23 · source: NVD
OS
Oncommand System Manager · Netapp
3.0.0 through 3.1.3 · source: NVD
SE
Sd-wan Edge · Oracle
9.0 · source: NVD
WM
Workload Manager · Oracle
18c; 19c · source: NVD
Affected product
TO
Tomcat
Apache
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-17527
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-17527
Mailing List
http://www.openwall.com/lists/oss-security/2020/12/03/3
lists.apache.org
https://lists.apache.org/thread.html/r26a2a66339087fc37db3caf201e446d3e83b5cce314371e235ff1784%40%3Ccommits.tomee.apache.org%3E
lists.apache.org
https://lists.apache.org/thread.html/r2d6e05c5ff96f8068a59dfdb3800e9ee8d4e36ce1971783c6e5f9b20%40%3Ccommits.tomee.apache.org%3E
lists.apache.org
https://lists.apache.org/thread.html/r5a285242737ddef4d338236328aaaf3237183e1465a5efafd16b99ed%40%3Cdev.tomcat.apache.org%3E
lists.apache.org
https://lists.apache.org/thread.html/r8a227ac6a755a6406c1cc47dd48800e973d4cf13fe7fe68ac59c679c%40%3Cdev.tomcat.apache.org%3E
lists.apache.org
https://lists.apache.org/thread.html/r9fd47f1b03e9b41d16a5cf72659b533887267d3398d963c2fff3abfa%40%3Ccommits.tomee.apache.org%3E
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