Affected versions: ≥ 3.1.4 and < 3.1.9
Full advisory: our disclosure post
CVE-2026-115451MediumCVSS 6.9CVE published 5 November 2026Added to mySites.guru 5 November 2026
Tassos Advanced Custom Fields (plg_system_acf) 3.1.4 to 3.1.8 and 2.8.13 to 2.8.15 - CVE-2026-115451 Unauthenticated Gallery Image Deletion
CVE-2026-115451 (CVSS 4.0 6.9 Medium) is an improper access control flaw in the Gallery field of Advanced Custom Fields for Joomla by Tassos Marinos. Anyone, without logging in, could delete images in the Gallery folders, including images already shown on published articles and modules. In ACF 3.1.7 and 3.1.8, users could also see, remove or save each other's unsaved uploads. The CVE lists ACF 3.1.4 to 3.1.8 and 2.8.13 to 2.8.15 as affected and credits Michael Nielsen. The vendor fixed it in 3.1.9 for Joomla 4 and later (4 November 2026) and in 2.8.16 for Joomla 3 (5 November 2026): an image can now only be removed from a gallery when the server issued a token for it. This is the Joomla extension from tassos.gr, NOT the WordPress plugin Advanced Custom Fields. On Joomla 4, 5 or 6 update Advanced Custom Fields to 3.1.9 or later; on Joomla 3 update to 2.8.16.
Is my site affected?
CVE-2026-115451 is checked by 4 rules. Find the extension and release line your site runs:
| Extension | Affected versions | Fixed in | What to do |
|---|---|---|---|
| Tassos Advanced Custom Fields | from 3.1.4 up to but not including 3.1.9 | 3.1.9 | Update Tassos Advanced Custom Fields to 3.1.9 or later. |
| Tassos Advanced Custom Fields | from 2.8.13 up to but not including 2.8.16 | 2.8.16 | Update Tassos Advanced Custom Fields to 2.8.16 or later. |
| Tassos Smile Pack | from 2.1.2 up to but not including 2.1.7 | 2.1.7 | Update Tassos Smile Pack to 2.1.7 or later. |
| Tassos Smile Pack | from 1.2.7 up to but not including 1.2.10 | 1.2.10 | Update Tassos Smile Pack to 1.2.10 or later. |
How CVE-2026-115451 is scored
The base metrics as Joomla CNA published them, and what each one means for a site running an affected version. Threat and environmental metrics are left out: they describe a moment or a particular install rather than the flaw.
6.9 Medium
CVSS 4.0, scored by Joomla CNACVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:NHow it is reached
- AV:N Attack vector
- Network. Reachable across the internet
- AC:L Attack complexity
- Low. Nothing to work around, it just works
- AT:N Attack requirements
- None. Works against any affected install
- PR:N Privileges required
- None. No account needed
- UI:N User interaction
- None. Nobody has to be tricked into anything
What it does to the site
- VC:L Confidentiality
- Low. Some data can be read
- VI:L Integrity
- Low. Some data can be altered
- VA:N Availability
- None. The site stays up
What it does beyond the site
- SC:N Confidentiality
- None. Other systems keep their data
- SI:N Integrity
- None. Other systems keep their integrity
- SA:N Availability
- None. Other systems stay up
Timeline
- 4 November 2026We published: Tassos ACF and Smile Pack for Joomla Fix Two CVEs: a Map XSS and Gallery Image Deletion
- 5 November 2026CVE-2026-115451 record published by its CNA
- 5 November 2026mySites.guru check added for Tassos Advanced Custom Fields (from 3.1.4 up to but not including 3.1.9)
- 5 November 2026mySites.guru check added for Tassos Advanced Custom Fields (from 2.8.13 up to but not including 2.8.16)
- 5 November 2026mySites.guru check added for Tassos Smile Pack (from 2.1.2 up to but not including 2.1.7)
- 5 November 2026mySites.guru check added for Tassos Smile Pack (from 1.2.7 up to but not including 1.2.10)
Rule details
Tassos Advanced Custom Fields - Tassos Advanced Custom Fields (plg_system_acf) 3.1.4 to 3.1.8 and 2.8.13 to 2.8.15 - CVE-2026-115451 Unauthenticated Gallery Image Deletion
CVE-2026-115451 (CVSS 4.0 6.9 Medium) is an improper access control flaw in the Gallery field of Advanced Custom Fields for Joomla by Tassos Marinos. Anyone, without logging in, could delete images in the Gallery folders, including images already shown on published articles and modules. In ACF 3.1.7 and 3.1.8, users could also see, remove or save each other's unsaved uploads. The CVE lists ACF 3.1.4 to 3.1.8 and 2.8.13 to 2.8.15 as affected and credits Michael Nielsen. The vendor fixed it in 3.1.9 for Joomla 4 and later (4 November 2026) and in 2.8.16 for Joomla 3 (5 November 2026): an image can now only be removed from a gallery when the server issued a token for it. This is the Joomla extension from tassos.gr, NOT the WordPress plugin Advanced Custom Fields. On Joomla 4, 5 or 6 update Advanced Custom Fields to 3.1.9 or later; on Joomla 3 update to 2.8.16.
Affected versions: ≥ 2.8.13 and < 2.8.16
Full advisory: our disclosure post
Tassos Smile Pack - Tassos Smile Pack (com_smilepack) 2.1.2 to 2.1.6 and 1.2.7 to 1.2.9 - CVE-2026-115451 Unauthenticated Gallery Image Deletion
CVE-2026-115451 (CVSS 4.0 6.9 Medium) is an improper access control flaw in the Gallery of Smile Pack for Joomla by Tassos Marinos, the same flaw fixed in Tassos Advanced Custom Fields this week. Anyone, without logging in, could delete images in the Gallery folders, including images already shown on published articles and modules. The CVE lists Smile Pack 2.1.2 to 2.1.6 and 1.2.7 to 1.2.9 as affected and credits Michael Nielsen. The vendor fixed it in Smile Pack 2.1.7 for Joomla 4 and later (4 November 2026) and in 1.2.10 for Joomla 3 (5 November 2026). On Joomla 4, 5 or 6 update Smile Pack to 2.1.7 or later; on Joomla 3 update to 1.2.10.
Affected versions: ≥ 2.1.2 and < 2.1.7
Full advisory: our disclosure post
Tassos Smile Pack - Tassos Smile Pack (com_smilepack) 2.1.2 to 2.1.6 and 1.2.7 to 1.2.9 - CVE-2026-115451 Unauthenticated Gallery Image Deletion
CVE-2026-115451 (CVSS 4.0 6.9 Medium) is an improper access control flaw in the Gallery of Smile Pack for Joomla by Tassos Marinos, the same flaw fixed in Tassos Advanced Custom Fields this week. Anyone, without logging in, could delete images in the Gallery folders, including images already shown on published articles and modules. The CVE lists Smile Pack 2.1.2 to 2.1.6 and 1.2.7 to 1.2.9 as affected and credits Michael Nielsen. The vendor fixed it in Smile Pack 2.1.7 for Joomla 4 and later (4 November 2026) and in 1.2.10 for Joomla 3 (5 November 2026). On Joomla 4, 5 or 6 update Smile Pack to 2.1.7 or later; on Joomla 3 update to 1.2.10.
Affected versions: ≥ 1.2.7 and < 1.2.10
Full advisory: our disclosure post
Our disclosure post
Other vulnerabilities in Tassos Advanced Custom Fields and Tassos Smile Pack
Updating for CVE-2026-115451 alone can leave a site on a release another rule still matches. These are the other flaws we check for in the same extensions.
Tassos Advanced Custom Fields
Latest safe version: 3.1.9
- CVE-2026-115452 High, from 3.0.0 up to but not including 3.1.9
Tassos Smile Pack
Latest safe version: 2.1.7
- CVE-2026-115452 High, from 2.0.0 up to but not including 2.1.7
References
- CVE-2026-115451 on cve.org (the official CVE record)
- CVE-2026-115451 in the NIST National Vulnerability Database
- Tassos ACF and Smile Pack for Joomla Fix Two CVEs: a Map XSS and Gallery Image Deletion
CVE-2026-115451 questions
Which versions are affected by CVE-2026-115451?
CVE-2026-115451 is covered by 4 rules: Tassos Advanced Custom Fields from 3.1.4 up to but not including 3.1.9; Tassos Advanced Custom Fields from 2.8.13 up to but not including 2.8.16; Tassos Smile Pack from 2.1.2 up to but not including 2.1.7; Tassos Smile Pack from 1.2.7 up to but not including 1.2.10.
How do I fix CVE-2026-115451?
It depends on the extension and release line your site runs. For Tassos Advanced Custom Fields from 3.1.4 up to but not including 3.1.9: update Tassos Advanced Custom Fields to 3.1.9 or later. For Tassos Advanced Custom Fields from 2.8.13 up to but not including 2.8.16: update Tassos Advanced Custom Fields to 2.8.16 or later. For Tassos Smile Pack from 2.1.2 up to but not including 2.1.7: update Tassos Smile Pack to 2.1.7 or later. For Tassos Smile Pack from 1.2.7 up to but not including 1.2.10: update Tassos Smile Pack to 1.2.10 or later.
How severe is CVE-2026-115451?
Joomla CNA scores it 6.9 (Medium) under CVSS 4.0. In plain terms: reachable across the internet, no account needed and nobody has to be tricked into anything.
Running an affected version on a site you manage?
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This check is part of the mySites.guru Joomla vulnerability scanner, which reads every installed extension's version on each audit. Browse the rest of the Joomla vulnerability database.
Rules current as of 15 November 2026.