CVE-2020-15249
Stored XSS by authenticated backend user with access to upload files
October is a free, open-source, self-hosted CMS platform based on the Laravel PHP Framework. In October CMS from version 1.0.319 and before version 1.0.469, backend users with access to upload files were permitted to upload SVG files without any sanitization applied to the uploaded files. Since SVG files support being parsed as HTML by browsers, this means that they could theoretically upload Javascript that would be executed on a path under the website's domain (i.e. /storage/app/media/evil.svg), but they would have to convince their target to visit that location directly in the target's browser as the backend does not display SVGs inline anywhere, SVGs are only displayed as image resources in the backend and are thus unable to be executed. Issue has been patched in Build 469 (v1.0.469) & v1.1.0.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Required
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Stored XSS by authenticated backend user with access to upload files
October is a free, open-source, self-hosted CMS platform based on the Laravel PHP Framework. In October CMS from version 1.0.319 and before version 1.0.469, backend users with access to upload files were permitted to upload SVG files without any sanitization applied to the uploaded files. Since SVG files support being parsed as HTML by browsers, this means that they could theoretically upload Javascript that would be executed on a path under the website's domain (i.e. /storage/app/media/evil.svg), but they would have to convince their target to visit that location directly in the target's browser as the backend does not display SVGs inline anywhere, SVGs are only displayed as image resources in the backend and are thus unable to be executed. Issue has been patched in Build 469 (v1.0.469) & v1.1.0.
- Record
CVE-2020-15249- CVSS 3.1
- 2.8 Low
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2020-1454
October is a free, open-source, self-hosted CMS platform based on the Laravel PHP Framework. In October CMS from version 1.0.319 and before version 1.0.469, backend users with access to upload files were permitted to upload SVG files without any sanitization applied to the uploaded files. Since SVG files support being parsed as HTML by browsers, this means that they could theoretically upload Javascript that would be executed on a path under the website's domain (i.e. /storage/app/media/evil.svg), but they would have to convince their target to visit that location directly in the target's browser as the backend does not display SVGs inline anywhere, SVGs are only displayed as image resources in the backend and are thus unable to be executed. Issue has been patched in Build 469 (v1.0.469) & v1.1.0.
- Record
EUVD-2020-1454- CVSS 3.1
- 2.8 Low
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-fx3v-553x-3c4q
Stored XSS by authenticated backend user with access to upload files
Impact
Backend users with access to upload files were permitted to upload SVG files without any sanitization applied to the uploaded files. Since SVG files support being parsed as HTML by browsers, this means that they could theoretically upload Javascript that would be executed on a path under the website's domain (i.e. /storage/app/media/evil.svg), but they would have to convince their target to visit that location directly in the target's browser as the backend does not display SVGs inline anywhere, SVGs are only displayed as image resources in the backend and are thus unable to be executed.
Patches
Issue has been patched in Build 469 (v1.0.469) & v1.1.0.
Workarounds
Apply https://github.com/octobercms/library/commit/80aab47f044a2660aa352450f55137598f362aa4 to your installation manually if unable to upgrade to Build 469 or v1.1.0.
References
Reported by Hoan Hoang
For more information
If you have any questions or comments about this advisory:
- Email us at [email protected]
Threat assessment:
<img width="1107" alt="Screen Shot 2020-10-10 at 1 47 49 PM" src="https://user-images.githubusercontent.com/7253840/95663787-378f2b80-0aff-11eb-8dfc-b97d162939da.png">
- Record
GHSA-fx3v-553x-3c4q- CVSS 3.1
- 2.8 Low
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
NVD
October is a free, open-source, self-hosted CMS platform based on the Laravel PHP Framework. In October CMS from version 1.0.319 and before version 1.0.469, backend users with access to upload files were permitted to upload SVG files without any sanitization applied to the uploaded files. Since SVG files support being parsed as HTML by browsers, this means that they could theoretically upload Javascript that would be executed on a path under the website's domain (i.e. /storage/app/media/evil.svg), but they would have to convince their target to visit that location directly in the target's browser as the backend does not display SVGs inline anywhere, SVGs are only displayed as image resources in the backend and are thus unable to be executed. Issue has been patched in Build 469 (v1.0.469) & v1.1.0.
- Record
CVE-2020-15249- CVSS 3.1
- 2.8 Low
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N - CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - CVSS 2.0
- 3.5 Low
AV:N/AC:M/Au:S/C:N/I:P/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
OSV
October is a free, open-source, self-hosted CMS platform based on the Laravel PHP Framework. In October CMS from version 1.0.319 and before version 1.0.469, backend users with access to upload files were permitted to upload SVG files without any sanitization applied to the uploaded files. Since SVG files support being parsed as HTML by browsers, this means that they could theoretically upload Javascript that would be executed on a path under the website's domain (i.e. /storage/app/media/evil.svg), but they would have to convince their target to visit that location directly in the target's browser as the backend does not display SVGs inline anywhere, SVGs are only displayed as image resources in the backend and are thus unable to be executed. Issue has been patched in Build 469 (v1.0.469) & v1.1.0.
- Record
CVE-2020-15249- CVSS 3.1
- 5.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
OSVGHSA-fx3v-553x-3c4q
Stored XSS by authenticated backend user with access to upload files
Impact
Backend users with access to upload files were permitted to upload SVG files without any sanitization applied to the uploaded files. Since SVG files support being parsed as HTML by browsers, this means that they could theoretically upload Javascript that would be executed on a path under the website's domain (i.e. /storage/app/media/evil.svg), but they would have to convince their target to visit that location directly in the target's browser as the backend does not display SVGs inline anywhere, SVGs are only displayed as image resources in the backend and are thus unable to be executed.
Patches
Issue has been patched in Build 469 (v1.0.469) & v1.1.0.
Workarounds
Apply https://github.com/octobercms/library/commit/80aab47f044a2660aa352450f55137598f362aa4 to your installation manually if unable to upgrade to Build 469 or v1.1.0.
References
Reported by Hoan Hoang
For more information
If you have any questions or comments about this advisory:
- Email us at [email protected]
Threat assessment:
<img width="1107" alt="Screen Shot 2020-10-10 at 1 47 49 PM" src="https://user-images.githubusercontent.com/7253840/95663787-378f2b80-0aff-11eb-8dfc-b97d162939da.png">
- Record
GHSA-fx3v-553x-3c4q- CVSS 3.1
- 2.8 Low
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
october/backendPackagist |
1.0.319 up to 1.0.469 | 1.0.469 |
october/backendPackagist |
1.0.319 up to 1.0.469, plus listed versions v1.0.319v1.0.320v1.0.321v1.0.322v1.0.323 Show 45 moreShow lessv1.0.324v1.0.325v1.0.326v1.0.327v1.0.328v1.0.329v1.0.330v1.0.331v1.0.332v1.0.333v1.0.334v1.0.335v1.0.336v1.0.337v1.0.338v1.0.339v1.0.340v1.0.341v1.0.342v1.0.343v1.0.344v1.0.345v1.0.346v1.0.347v1.0.348v1.0.349v1.0.350v1.0.351v1.0.352v1.0.353v1.0.354v1.0.355v1.0.356v1.0.357v1.0.358v1.0.359v1.0.360v1.0.361v1.0.362v1.0.363v1.0.364v1.0.365v1.0.366v1.0.367v1.0.368 |
1.0.469 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2020-15249 is a low vulnerability (CVSS 2.8) in Octobercms October, published November 23, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.46%, the 40th percentile. Fixed in october/backend 1.0.469.
References
Left out here: 100 versions. The JSON record has them.