CVE-2020-13943

CVE-2020-13943

Medium · published October 12, 2020

Patch now

High probability of exploitation

CVSS calls it medium at 4.3. It sits in the 99.0th percentile for exploit probability.

CVSS v3.1
4.3
EPSS
55%
Percentile
99.0
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
4.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
CVSS v4.0
Not supplied
EPSS
0.54966 · 99.0th percentile
Published
2020-10-12T18:15Z
Affected products (131)
ProductVersionsFixed in
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References (14)
EPSS history
Timeline
  • 12 OCT 13:46Z
    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…
    cvelistv5