Skip to content
Fencer Intel
medium 6.5

CVE-2026-19856 json

All in One SEO < 5.0.2.1 - Unauthenticated Arbitrary Shortcode Execution via Search Query

published last mo. modified last mo. also EUVD-2026-91769

cvss
6.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 7%
public exploits
0
none known

Summary

The All in One SEO WordPress plugin before 5.0.2.1 does not correctly determine which shortcodes are present in content derived from user input before deciding which ones to strip, allowing unauthenticated users to execute arbitrary shortcodes registered on the site. On sites upgraded from older versions the protection is disabled outright, making the issue reachable without any crafted input.

Patch / fix

  • Unknown All in One SEO 5.0.2.1

Is CVE-2026-19856 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
last mo.

Exploit prediction

0.18% chance of exploitation in the next 30 days, higher than 7% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • wpscan.com https://wpscan.com/vulnerability/e35365d3-65de-45a7-9629-17aacd5299c7/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Affected products

  • Unknown All in One SEO

Classification

Weakness
  • CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component
Technology feeds

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.