Cisco Email Security Appliance URL Filtering Bypass Vulnerability
Published Oct 5, 2018
5.3
MEDIUMCVSS 3.0
EPSS 2.28%
Description
A vulnerability in the anti-spam protection mechanisms of Cisco AsyncOS Software for the Cisco Email Security Appliance (ESA) could allow an unauthenticated, remote attacker to bypass certain content filters on an affected device. The vulnerability is due to incomplete input and validation checking mechanisms for certain Sender Policy Framework (SPF) messages that are sent to an affected device. An attacker could exploit this vulnerability by sending a customized SPF packet to an affected device. If successful, an exploit could allow the attacker to bypass the URL filters that are configured for the affected device, which could allow malicious URLs to pass through the device.
Affected products
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||
|---|---|---|---|---|---|---|
| Cisco | Cisco Email Security Appliance (ESA) | n/a |
|
- n/a
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:N/I:L/A:N
AV:N/AC:L/Au:N/C:N/I:P/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 25, 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 v5
Percentile over time
- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v5
Table of values (19 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 2.28% (0.02276) | 82.48th | v5 (v2026.06.15) |
| Jun 15, 2026 | 2.28% (0.02276) | 80.77th | v5 (v2026.06.15) |
| Jul 20, 2024 | 0.11% (0.00114) | 45.51th | v3 (v2023.03.01) |
| Jun 20, 2024 | 0.11% (0.00114) | 45.28th | v3 (v2023.03.01) |
| Apr 24, 2024 | 0.16% (0.00159) | 51.91th | v3 (v2023.03.01) |
| Mar 7, 2024 | 0.29% (0.00295) | 68.61th | v3 (v2023.03.01) |
| Feb 8, 2024 | 0.42% (0.00418) | 73.45th | v3 (v2023.03.01) |
| Sep 29, 2023 | 0.39% (0.00393) | 70.29th | v3 (v2023.03.01) |
| Aug 11, 2023 | 0.38% (0.00376) | 69.27th | v3 (v2023.03.01) |
| Jul 8, 2023 | 0.40% (0.00400) | 70.00th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.25% (0.00247) | 60.83th | 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 | 1.05% (0.01046) | 28.66th | v1 |
| Jan 6, 2022 | 1.05% (0.01046) | 28.03th | v1 |
| Sep 1, 2021 | 1.05% (0.01046) | 65.02th | v1 |
| Apr 14, 2021 | 1.05% (0.01046) | 0.00th | v1 |
References (3)
- http://www.securityfocus.com/bid/105300 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- http://www.securitytracker.com/id/1041687 vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180905-esa-url-bypass vendor-advisoryx_refsource_CISCOVendor Advisory
| Link | Providers | Tags |
|---|---|---|
| http://www.securityfocus.com/bid/105300 | vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry | |
| http://www.securitytracker.com/id/1041687 | vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry | |
| https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180905-esa-url-bypass | vendor-advisoryx_refsource_CISCOVendor Advisory |
Change history (0)
No recorded changes yet.