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Threats / Mirasvit / CVE-2026-45247
CVE-2026-45247 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-06

Mirasvit Full Page Cache Warmer vulnerability

Mirasvit Full Page Cache Warmer contains a deserialization vulnerability allowing unauthenticated remote code execution via crafted serialized PHP objects in the CacheWarmer cookie.

Verdict

Today item — known-exploited.

An unauthenticated attacker can exploit unsafe deserialization of untrusted data to execute arbitrary code on affected systems. The vulnerability is actively exploited in the wild with low EPSS probability but demonstrates real-world attack activity.

CISA KEV Yes · 2026-06-033EPSS 0.06149 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2026-06-03).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.06149 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
FIRST EPSS ↗High
Severity / affected
Affected: Mirasvit, Mirasvit Full Page Cache Warmer. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-502 Deserialization of Untrusted Data — weakness family: Injection.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-502 · Deserialization of Untrusted DataInjection
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution not established

No threat-actor attribution is established from the public feed for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.

03

Why it matters

— the attack path, told twice: adversary, then board
1

Front door — unauthenticated access narrative 1

Attacker
I craft a malicious serialized PHP object and inject it into the CacheWarmer cookie to trigger unsafe deserialization.
Business
Attackers gain unauthenticated remote code execution on web servers running the vulnerable extension, enabling full system compromise.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I execute arbitrary PHP code within the application context to establish persistence and lateral movement.
Business
Threat actors obtain persistent access to infrastructure, customer data, and internal systems without authentication barriers.
3

Lateral reach — past segmentation narrative 3

Attacker
I exfiltrate sensitive data or deploy additional malware payloads across the compromised environment.
Business
Organizations face data breaches, operational disruption, and potential regulatory penalties from unauthorized system access.
04

What to do

— defensible action
  • Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05

Coverage & confidence

— what we know, and what we don’t

Established (cited)

  • KEV listing (CISA)
  • EPSS probability (FIRST)
  • CWE weakness mapping (NVD)
  • Catalogued by VulnCheck (CNA)
  • Named finder/reporter credit (CVE.org)

    • Coverage gaps — stated, not hidden

  • No EUVD / GCVE mirror in feed — single-authority dependency for the identifier.
  • EPSS & exposure are time-varying; verify live at the source.
  • Threat-actor attribution not established from feed data — absence of a name is not absence of compromise.
    • Disclosure & credit2
    Catalogued by VulnCheckCNA
    Credited with finding itSansecfinder