A vulnerability in traffic-monitoring functions in Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to circumvent Layer 4 Traffic Monitor (L4TM) functionality and bypass security protections
Published Jun 7, 2018
7.5
HIGHCVSS 3.0
EPSS 3.84%
Description
A vulnerability in traffic-monitoring functions in Cisco Web Security Appliance (WSA) could allow an unauthenticated, remote attacker to circumvent Layer 4 Traffic Monitor (L4TM) functionality and bypass security protections. The vulnerability is due to a change in the underlying operating system software that is responsible for monitoring affected traffic. An attacker could exploit this vulnerability by sending crafted IP packets to an affected device. A successful exploit could allow the attacker to pass traffic through the device, which the WSA was configured to deny. This vulnerability affects both IPv4 and IPv6 traffic. This vulnerability affects Cisco AsyncOS versions for WSA on both virtual and hardware appliances running any release of the 10.5.1, 10.5.2, or 11.0.0 WSA Software. The WSA is vulnerable if it is configured for L4TM. Cisco Bug IDs: CSCvg78875.
Affected products
- Vendor n/a Product Cisco Web Security Appliance unknown Defaultn/a
- Version Cisco Web Security Appliance unknownStatusaffectedConstraints-
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| n/a | Cisco Web Security Appliance unknown | n/a |
|
- 10.5.1
- 10.5.1-296
- 10.5.2
- 11.0.0
- 11.5.0-fcs-442
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
AV:N/AC:L/Au:N/C:P/I:N/A:N
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
YesTechnical Impact
PartialDecision
n/aAssessed Nov 29, 2024 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (21 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 3.84% (0.03839) | 89.78th | v5 (v2026.06.15) |
| Aug 23, 2026 | 2.86% (0.02862) | 85.64th | v5 (v2026.06.15) |
| Jun 15, 2026 | 3.89% (0.03889) | 88.85th | v5 (v2026.06.15) |
| Mar 30, 2025 | 1.24% (0.01245) | 77.45th | v4 (v2025.03.14) |
| Mar 29, 2025 | 2.28% (0.02282) | 74.44th | v4 (v2025.03.14) |
| Jul 20, 2024 | 0.14% (0.00143) | 50.53th | v3 (v2023.03.01) |
| Dec 8, 2023 | 0.14% (0.00143) | 49.83th | v3 (v2023.03.01) |
| Oct 29, 2023 | 0.16% (0.00157) | 51.98th | v3 (v2023.03.01) |
| Jul 8, 2023 | 0.23% (0.00233) | 60.28th | v3 (v2023.03.01) |
| Jul 6, 2023 | 0.42% (0.00418) | 70.56th | v3 (v2023.03.01) |
| Jun 1, 2023 | 0.42% (0.00424) | 70.62th | v3 (v2023.03.01) |
| May 8, 2023 | 0.48% (0.00485) | 72.37th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.27% (0.00270) | 62.66th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.14% (0.01136) | 59.45th | v2 (v2022.01.01) |
| Oct 18, 2022 | 1.14% (0.01136) | 58.28th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.14% (0.01136) | 56.27th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.14% (0.01136) | 34.23th | v2 (v2022.01.01) |
| Feb 3, 2022 | 1.11% (0.01110) | 29.52th | v1 |
| Jan 6, 2022 | 1.11% (0.01110) | 28.89th | v1 |
| Sep 1, 2021 | 1.11% (0.01110) | 66.78th | v1 |
| Apr 14, 2021 | 1.11% (0.01110) | 0.00th | v1 |
References (3)
- http://www.securityfocus.com/bid/104417 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- http://www.securitytracker.com/id/1041081 vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180606-wsa x_refsource_CONFIRMVendor Advisory
| Link | Providers | Tags |
|---|---|---|
| http://www.securityfocus.com/bid/104417 | vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry | |
| http://www.securitytracker.com/id/1041081 | vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry | |
| https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180606-wsa | x_refsource_CONFIRMVendor Advisory |
Change history (0)
No recorded changes yet.