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Threats / Mirasvit / CVE-2026-45247
CVE-2026-45247 · EUVD no mirror located · GCVE no mirror located Verified 2026-08-04

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 · 2026-06-035EPSS 0.27546 (verify live)6Exploit Weaponized · public PoC7CVSS 9.33CISA SSVC Exploitation: active · Automatable: yes · Impact: total4
01

Is it exploitable?

— the evidence, ranked above the score
Exploit available
Fully weaponized — public exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
vulncheck.com ↗Confirmed
Reported exploitation
3 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
imperva.com ↗cisa.gov ↗recordedfuture.com ↗Confirmed
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2026-06-03).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.27546 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
FIRST EPSS ↗High
Severity / affected
CVSS 9.3 (CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N) · Affected: Mirasvit, Mirasvit Full Page Cache Warmer. Confirm exact fixed builds in the vendor advisory.CVSS — CNA-assigned (CVE.org), version 4.0, set at disclosure.
CVE.org ↗Reported
Weakness (CWE)
Mapped to CWE-502 Deserialization of Untrusted Data — weakness family: Injection.CWE — CNA-assigned (CVE.org); the weakness class drives how the flaw is exploited.
CVE.org ↗Reported
CISA SSVC (triage disposition)
Exploitation: active · Automatable: yes · Technical Impact: totalCISA's own stakeholder-specific triage inputs, published in the CVE record (CISA Coordinator role). NOTE: this is CISA's three decision points; the final Act/Attend/Track decision also requires a Mission & Well-being input not published here, so no overall decision is asserted.
CISA-ADP ↗Reported
Currency of the record
CISA added this to its KEV catalog 8 days after the CVE record was published.KEV lag = CISA-KEV dateAdded − CVE.org datePublished; a floor on how long the known-exploited flaw sat in the public record before the federal catalog listed it. Severity/weakness here is CNA- or CISA-assigned (current at disclosure), independent of NVD's analysis backlog.
CISA KEV ↗CVE.org ↗Reported
WeaknessCWE-502 · Deserialization of Untrusted DataInjection
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution not established

No confirmed (advisory-backed) threat-actor attribution is established 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)
  • Weaponized exploit available (VulnCheck)
  • 3 reported-exploitation source(s)
  • CVSS 9.3 — CNA-assigned (CVE.org)
  • CISA SSVC triage disposition (CVE.org ADP)
  • CWE weakness mapping — CNA-assigned (CVE.org)
  • Public exploit availability
  • 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