High severity · published Jun 30, 2021
CVE-2021-32567
Improper Input Validation vulnerability in HTTP/2 of Apache Traffic Server allows an attacker to DOS the server
7.5
CVSS
2.4%
EPSS
No
On KEV
Description
Improper Input Validation vulnerability in HTTP/2 of Apache Traffic Server allows an attacker to DOS the server. This issue affects Apache Traffic Server 7.0.0 to 7.1.12, 8.0.0 to 8.1.1, 9.0.0 to 9.0.1.
CVSS vector
CVSS:3.1/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)2.4% · higher than 84% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
10.0 · source: NVD
TS
Traffic Server · Apache
7.0.0 through 7.1.12; 8.0.0 through 8.1.1; 9.0.0 through 9.0.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-32567
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-32567
Mailing List
https://lists.apache.org/thread.html/ra1a41ff92a70d25bf576d7da2590575e8ff430393a3f4a0c34de4277%40%3Cusers.trafficserver.apache.org%3E
Third Party Advisory
https://www.debian.org/security/2021/dsa-4957
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10.0
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9.8
CVE-2026-58185
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9.8
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