CVE-2026-111658
SiteServer SSCMS through 7.4.0 Cross-Site Authorization Bypass via Channels API
SiteServer SSCMS through 7.4.0 contains an authorization bypass vulnerability in ChannelsController that allows site-scoped administrators to access other sites' channels by supplying foreign channel IDs. Attackers with Channels permission on one site can read and overwrite another site's channel names, file paths, templates, link URLs, and custom fields, breaking multi-site isolation.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- High
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
5.1
SiteServer SSCMS through 7.4.0 Cross-Site Authorization Bypass via Channels API
SiteServer SSCMS through 7.4.0 contains an authorization bypass vulnerability in ChannelsController that allows site-scoped administrators to access other sites' channels by supplying foreign channel IDs. Attackers with Channels permission on one site can read and overwrite another site's channel names, file paths, templates, link URLs, and custom fields, breaking multi-site isolation.
- Record
CVE-2026-111658- CVSS 4.0
- 5.1 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 3.8 Low
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-639
- Updated
- 2026-11-02
EUVDEUVD-2026-103080
5.1
SiteServer SSCMS through 7.4.0 contains an authorization bypass vulnerability in ChannelsController that allows site-scoped administrators to access other sites' channels by supplying foreign channel IDs. Attackers with Channels permission on one site can read and overwrite another site's channel names, file paths, templates, link URLs, and custom fields, breaking multi-site isolation.
- Record
EUVD-2026-103080- CVSS 4.0
- 5.1 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-f64v-vg62-99f4
5.1
SiteServer SSCMS through 7.4.0 contains an authorization bypass vulnerability in...
SiteServer SSCMS through 7.4.0 contains an authorization bypass vulnerability in ChannelsController that allows site-scoped administrators to access other sites' channels by supplying foreign channel IDs. Attackers with Channels permission on one site can read and overwrite another site's channel names, file paths, templates, link URLs, and custom fields, breaking multi-site isolation.
- Record
GHSA-f64v-vg62-99f4- CVSS 4.0
- 5.1 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 3.8 Low
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-639
- Updated
- 2026-11-02
NVD
5.1
SiteServer SSCMS through 7.4.0 contains an authorization bypass vulnerability in ChannelsController that allows site-scoped administrators to access other sites' channels by supplying foreign channel IDs. Attackers with Channels permission on one site can read and overwrite another site's channel names, file paths, templates, link URLs, and custom fields, breaking multi-site isolation.
- Record
CVE-2026-111658- CVSS 4.0
- 5.1 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 3.8 Low
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-639
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-111658 is a medium vulnerability (CVSS 5.1) in Siteserver Sscms, published October 16, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.33%, the 25th percentile. No source names a fixed version.
References
hackmd.io/@hieuPenguinnn/sscms-cross-site-channel-idor
github.com/siteserver/cms/blob/sscms-v7.2.1/src/SSCMS.Web/Controllers/Admin/Cms/Channels/ChannelsController.Update.cs
github.com/siteserver/cms/blob/sscms-v7.2.1/src/SSCMS.Web/Controllers/Admin/Cms/Channels/ChannelsController.Get.cs
vulncheck.com/advisories/siteserver-sscms-through-7.4.0-cross-site-authorization-bypass-via-channels-api
nvd.nist.gov/vuln/detail/CVE-2026-111658
github.com/advisories/GHSA-f64v-vg62-99f4