WPO365 LOGIN before 45.2 SAML Replay Protection Bypass
Affects WPO365 | LOGIN plugin versions before 45.2 where SAML SSO is in use. Fixed in 45.2. No vendor rating is given, so the CVSS score of 9.1 (critical) is the only severity figure.
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- Fixed in 45.2
- Who is exposed
- Not reported
Do first: Upgrade to a fixed version: 45.2.
- Exploitation?/40Exploitation: unknown (data gap). No CISA SSVC exploitation rating yet
- Exposure17/25No login or user action needed, reachable over the network without a login · Data gap: Advisories don't say whether default setups are affected
- Reach?/20Reach: unknown (data gap). No tracked technology or package matched
- Severity9.1/10CVSS 9.1
- No patch0/5No signal
What would change the score
- Would score about 71 if added to CISA KEV
- Would score about 66 if CISA's SSVC rates exploitation active
- Would score about 31 if advisories confirm default setups are exposed
CVE-2026-122220 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 9.1 (critical) and affects WPO365 | SEAMLESS WORDPRESS + MICROSOFT INTEGRATION (WPO365 | LOGIN); fixed in 45.2.
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- Published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 26/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Unclear
- Fix
- Fixed in 45.2
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
WPO365 | LOGIN (wpo365-login) WordPress plugin versions before 45.2 let remote attackers without logging in replay a captured, validly signed SAML login response to log in as the victim, including administrators. The anti-replay check never records processed SAML message IDs, so repeated replays within the assertion's validity window go undetected.
Read the original description
WPO365 | LOGIN (wpo365-login) plugin before version 45.2 contains an authentication bypass by capture-replay vulnerability caused by a non-functional anti-replay check in Saml2_Service::check_message_id(), which never persists processed SAML message IDs to the wpo365_saml_message_ids transient due to a logic error that returns before saving. Attackers who capture a validly-signed SAMLResponse can replay it to the ACS endpoint repeatedly within its assertion validity window to log in as the victim, including administrators, without detection since the duplicate message ID check never triggers.
What to do
Upgrade to a fixed version: 45.2.
Timeline
- CVE published
- First seen by cve.now
- Posted on X by cve.now
Affected versions
- wpo365 WPO365 | SEAMLESS WORDPRESS + MICROSOFT INTEGRATION (WPO365 | LOGIN)
fixed in 45.2
Evidence 3
- Patch
- Report
- Link
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-122220
Is CVE-2026-122220 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
What does this mean?
A captured SAML login response can be sent again to the plugin's login endpoint within its validity window. The plugin does not detect the replay, so the attacker can log in as the victim, including administrators.Source: vulncheck.com
Which versions are affected by CVE-2026-122220?
WPO365 | SEAMLESS WORDPRESS + MICROSOFT INTEGRATION (WPO365 | LOGIN): before 45.2.Source: cve.now feed data
Am I affected, and how do I check?
Versions of the WPO365 | LOGIN plugin (wpo365-login) before 45.2 are affected, and only sites that use SAML SSO are in scope. To check, look at the installed plugin version in the WordPress Plugins screen and whether SAML SSO is enabled in the plugin settings.Source: vulncheck.com
How do I fix CVE-2026-122220?
Update the WPO365 | LOGIN plugin to version 45.2 or later, which contains the fix.Source: vulncheck.com