Critical severity · published Jun 10, 2021
CVE-2021-26691
In Apache HTTP Server versions 2.4.0 to 2.4.46 a specially crafted SessionHeader sent by an origin server could cause a heap overflow
9.8
CVSS
68.3%
EPSS
No
On KEV
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)68.3% · higher than 99% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
HS
HTTP Server · Apache
2.4.0 through 2.4.46 · source: NVD
CB
Cloud Backup · Netapp
All versions, or not specified · source: NVD
DL
Debian Linux · Debian
9.0; 10.0 · source: NVD
EM
Enterprise Manager Ops Center · Oracle
12.4.0.0 · source: NVD
FE
Fedora · Fedoraproject
34; 35 · source: NVD
IE
Instantis Enterprisetrack · Oracle
17.1; 17.2; 17.3 · source: NVD
SB
Secure Backup · Oracle
before 18.1.0.1.0 · source: NVD
ZS
Zfs Storage Appliance Kit · Oracle
8.8 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-26691
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-26691
Vendor Advisory
http://httpd.apache.org/security/vulnerabilities_24.html
Mailing List
http://www.openwall.com/lists/oss-security/2021/06/10/7
lists.apache.org
https://lists.apache.org/thread.html/r50cae1b71f1e7421069036b213c26da7d8f47dd59874e3bd956959fe%40%3Cannounce.httpd.apache.org%3E
lists.apache.org
https://lists.apache.org/thread.html/r7f2b70b621651548f4b6f027552f1dd91705d7111bb5d15cda0a68dd%40%3Cdev.httpd.apache.org%3E
Mailing List
https://lists.apache.org/thread.html/re026d3da9d7824bd93b9f871c0fdda978d960c7e62d8c43cba8d0bf3%40%3Ccvs.httpd.apache.org%3E
Mailing List
https://lists.debian.org/debian-lts-announce/2021/07/msg00006.html
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