CVE-2024-20342 [Medium] | Security Bypass in Snort

Multiple Cisco products are affected by a vulnerability in the rate filtering feature of the Snort detection engine that could allow an unauthenticated, remote attacker to bypass a configured rate limiting filter.  This vulnerability is due to an incorrect connection count comparison. An attacker could exploit this vulnerability by sending traffic through an affected device at a rate that exceeds a configured rate filter. A successful exploit could allow the attacker to successfully bypass the rate filter. This could allow unintended traffic to enter the network protected by the affected device.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.05%	0.51%	+0.46%
2	2026-04-05	0.04%	0.05%	+0.02%
3	2025-12-01	—	0.04%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.05%

0.51%

+0.46%

2026-04-05

0.04%

0.05%

+0.02%

2025-12-01

—

0.04%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
5.8	3.1	MEDIUM	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:N) No account or special rights needed—anonymous or random user is enough. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:C) Breaking this can reach past the original component and bite other resources—bigger blast radius. Confidentiality (C:N) Doesn’t really leak secrets in a meaningful way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:L) Might cause slowdowns, glitches, or partial disruption—not a full brick.	3.9	1.4	[email protected]
8.6	3.1	HIGH	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:N) No account or special rights needed—anonymous or random user is enough. User interaction (UI:N) Nobody has to click “OK” or open a trap file; it can work without a victim helping. Scope (S:C) Breaking this can reach past the original component and bite other resources—bigger blast radius. Confidentiality (C:N) Doesn’t really leak secrets in a meaningful way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:N) Service keeps running; no real outage angle.	3.9	4.0	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

5.8

3.1

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L Click to expand

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N): No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C): Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N): Doesn’t really leak secrets in a meaningful way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:L): Might cause slowdowns, glitches, or partial disruption—not a full brick.

3.9

1.4

[email protected]

8.6

3.1

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N Click to expand

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N): No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N): Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C): Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N): Doesn’t really leak secrets in a meaningful way.
Integrity (I:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N): Service keeps running; no real outage angle.

3.9

4.0

[email protected]

OS Trackers for CVE-2024-20342

vendor	priority	summary	link
`alpine`	—	CVE-2024-20342: 1 source package rows (snort); 1 state rows across 1 repos (3.19-main); fixed 0, open 1.	https://security.alpinelinux.org/vuln/CVE-2024-20342

Affected software / configurations for CVE-2024-20342

Vendor	Product	Version	Raw CPE
cisco	snort	>= 3.0.0.0, < 3.1.74.0	cpe:2.3:a:cisco:snort::::::::
cisco	firepower_threat_defense_software	< 7.0.6.2	cpe:2.3:a:cisco:firepower_threat_defense_software::::::::
cisco	firepower_threat_defense_software	>= 7.2.0, < 7.2.6	cpe:2.3:a:cisco:firepower_threat_defense_software::::::::
cisco	firepower_threat_defense_software	>= 7.4.0, < 7.4.2	cpe:2.3:a:cisco:firepower_threat_defense_software::::::::
cisco	firepower_threat_defense_software	7.1.0	cpe:2.3:a:cisco:firepower_threat_defense_software:7.1.0:::::::*
cisco	firepower_threat_defense_software	7.3.0	cpe:2.3:a:cisco:firepower_threat_defense_software:7.3.0:::::::*

References for CVE-2024-20342

URL	Tags
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-snort-rf-bypass-OY8f3pnM	Vendor Advisory

URL

CVE-2024-20342 | Cisco Firepower Threat Defense Software Rate Filter Bypass Vulnerability

Exploit prediction scoring system (EPSS) score for CVE-2024-20342

Common vulnerability scoring system (CVSS) metrics for CVE-2024-20342

Weakness enumeration for CVE-2024-20342

OS Trackers for CVE-2024-20342

Affected software / configurations for CVE-2024-20342

References for CVE-2024-20342