CVE-2026-88798: medium-severity vulnerability in Really Simple Security
Really Simple Security (Free) < 9.8.3 - Unauthenticated Unbounded Option Growth via Spoofed Client IP Header
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
33Vexday Risk Score
No sign of exploitation. It has a public proof of concept.
ssvc Attendcvss 5.3epss 0.4%
The Really Simple Security WordPress plugin before 9.8.3 does not validate a client-supplied address value before using it as a storage key in one of its own options, allowing unauthenticated attackers to grow that option without bound and to slow the site's handling of missing pages.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Affected products
Unknown · Really Simple Securitypublic PoCs found — 1
cve_referencewpscan.com/vulnerability/e658dcd2-2ff6-4611-a28d-e2482c65be8b/unverified⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
Related CVEs — Really Simple Security
In the same product, most dangerous first.
CVE-2026-81766MEDIUMReally Simple Security < 9.8.0 - Multisite Subsite Admin+ Arbitrary Plugin Installation via rsp_upgrade_install_pluginEPSS 0.4%CVE-2026-89080HIGHReally Simple Security < 9.8.1 - Unauthenticated 2FA Bypass via Email Provider State DemotionEPSS 0.3%CVE-2026-8293HIGHReally Simple Security < 9.5.10.1 - Authentication Bypass via Two-Factor OTP SkipEPSS 0.2%