Medium severity · published Oct 21, 2020
CVE-2020-3299
Multiple Cisco products are affected by a vulnerability in the Snort detection engine that could allow an unauthenticated, remote attacker to bypass a configured File Policy for…
5.8
CVSS
2.3%
EPSS
No
On KEV
Description
Multiple Cisco products are affected by a vulnerability in the Snort detection engine that could allow an unauthenticated, remote attacker to bypass a configured File Policy for HTTP. The vulnerability is due to incorrect detection of modified HTTP packets used in chunked responses. An attacker could exploit this vulnerability by sending crafted HTTP packets through an affected device. A successful exploit could allow the attacker to bypass a configured File Policy for HTTP packets and deliver a malicious payload.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)2.3% · higher than 83% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SF
Secure Firewall Threat Defense · Cisco
6.0.0 before 6.3.0.1 · source: NVD
SN
Snort · Snort
before 2.9.13.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-3299
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-3299
lists.debian.org
https://lists.debian.org/debian-lts-announce/2023/02/msg00011.html
Vendor Advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-bypass-3eCfd24j
www.debian.org
https://www.debian.org/security/2023/dsa-5354
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