CVE-2026-76214
CVE-2026-76214 — phpMyFAQ before 4.1.7 WebAuthn Replay Attack via Challenge
phpMyFAQ before 4.1.7 (affected versions <= 4.1.5) fails to persist the WebAuthn login challenge generated by prepareForLogin, because neither WebAuthn controller saves the mutated key objects back to the database. At login the anti-replay comparison is skipped by its own null guard, allowing an attacker who captures a successful WebAuthn assertion to replay it indefinitely and authenticate as the user without any interaction or hardware key.
Published Updated Sources: NVD, thorsten (CNA), GitHub, GitHub Security Advisory, SOCRadar CTI
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.
Exploitation
Unreported
no source claims exploitation
EPSS
0%
ahead of 0% of scored CVEs
CVSS base
7.4
high · 2 sources
Remediation
The vendor's own words where we have them.
Upgrade phpMyFAQ to a fixed release (4.1.7). Apply vendor patches per advisory and restrict external exposure of the affected component until patched.
First 24 hours
Ordered from the record's own fields — exposure first, because you cannot patch what you have not found.
- Identify exposed assets running affected vendor/product/version combinations.
- Prioritize based on EPSS, PoC availability, and external exposure.
- Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class.
Affected scope
Vendor, product and version as the advisories word them.
| Vendor | Product | Versions | Status |
|---|---|---|---|
| thorsten | phpMyFAQ | 0 to < 4.1.7 | Vulnerable |
| thorsten | phpMyFAQ | 4.1.7 | Patched |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Availability
None
Confidentiality
High
Integrity
High
Scope
Unchanged
Attack Complexity
High
Attack Vector
Network
Privileges Req
None
User Interaction
None
Every base score collected
Sources score independently and disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Source |
|---|---|---|---|---|---|
| 7.4 | CVSS 3.1 | high | 2.2 | 5.2 | NVD, thorsten (CNA), GHSA |
| 9.1 | CVSS 4.0 | critical | — | — | thorsten (CNA) |
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
What this weakness leads to
MITRE's own consequences and mitigations for the weakness class — the authority's wording, not guidance derived from the CVSS vector.
CWE-294 · Authentication Bypass by Capture-replay
- Gain Privileges or Assume Identity
Mitigation: Utilize some sequence or time stamping functionality along with a checksum which takes this into account in order to ensure that messages can be parsed only once.
Weakness & attack patterns
- CWE-294
Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.
- T1558.003Steal or Forge Kerberos Tickets: Kerberoasting
- T1021Remote Services
- T1114.002Email Collection: Remote Email Collection
Detection
Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.
- Prioritize edge telemetry for network-reachable phpMyFAQ.
Timeline
What happened to this CVE, newest first — with the readings a source repeats on a schedule counted underneath rather than listed.
- 2026
Added · CVSS 3.1 7.4 (AV:N)
Aug 19, 2026 · NVD
Initial · CVE published
Aug 19, 2026 · NVD
Added · GHSA-wg4g-rgc9-r6gj published (critical)
Aug 19, 2026 · GitHub Security Advisory
References
4 on the record
- github.com/thorsten/phpMyFAQ/security/advisories/GHSA-f534-wv9g-wx2w
Exploit, Third Party Advisory, Mitre
- www.vulncheck.com/advisories/phpmyfaq-before-webauthn-replay-attack-via-challenge
Vendor Advisory, Mitre
- nvd.nist.gov/vuln/detail/CVE-2026-76214
NVD
- github.com/advisories/GHSA-wg4g-rgc9-r6gj
Exploit, Third Party Advisory
Elsewhere on this site
- thorstenevery CVE for this vendor
- Remote Code Execsame class
- CWE-294other pages naming this weakness
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record1
What should defenders know first?
CVE-2026-76214 is phpMyFAQ before 4.1.7 WebAuthn Replay Attack via Challenge, a high vulnerability affecting phpMyFAQ from thorsten. The current evidence does not list it in CISA KEV, and the exploit status is: Active exploitation is not confirmed from current sources for CVE-2026-76214. Public exploit evidence is: A public PoC is not confirmed from current sources for CVE-2026-76214. The affected-version evidence is listed in the key facts and affected products tables. Defenders should first verify whether exposed or business-critical assets run those versions, then apply vendor patches or mitigations, restrict reachable attack surface, and preserve logs for detection review. CVSS 7.4 describes technical severity, while EPSS 0% helps estimate near-term exploit likelihood; neither replaces asset context. Unknown fields should remain explicit in tickets, and threat actor, IOC, victimology, or payload claims should not be added unless a cited source supports them. Monitor CISA KEV, vendor advisories, NVD changes, public PoC repositories, and internal telemetry for update triggers.