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Threats / Adobe / CVE-2018-4990
CVE-2018-4990 · EUVD no mirror located · GCVE no mirror located Verified 2026-08-04

Adobe Acrobat and Reader vulnerability

Adobe Acrobat and Reader contain a double free vulnerability (CWE-415) that could enable remote code execution when processing malicious documents.

Verdict

Today item — known-exploited.

A double free memory corruption flaw in Adobe's PDF readers allows attackers to execute arbitrary code by crafting specially designed PDF files. The vulnerability has been observed in active exploitation in the wild.

CISA KEV Yes · 2022-06-084EPSS 0.36365 (verify live)5CVSS 8.8 (CISA)3CISA SSVC Exploitation: active · Automatable: no · Impact: total3
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
2 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-06-08).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.36365 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
CVSS 8.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H) · Affected: Adobe, Acrobat and Reader. Confirm exact fixed builds in the vendor advisory.CVSS — CISA-assigned via the ADP container (CVE.org), version 3.1; the CNA left no metrics, so CISA's own score is used ahead of NVD.
CISA-ADP ↗Reported
Weakness (CWE)
Mapped to CWE-415 Double Free — weakness family: Memory safety.CWE assignment from the public NVD record (may be stale); the weakness class drives how the flaw is exploited.
NVD ↗Reported
CISA SSVC (triage disposition)
Exploitation: active · Automatable: no · 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 1430 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.
WeaknessCWE-415 · Double FreeMemory safety
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 PDF document that triggers a double free condition in the memory allocator.
Business
Users receive seemingly legitimate PDF files that exploit this flaw when opened.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I distribute the malicious PDF through email, web downloads, or document sharing platforms.
Business
Attack surface expands across customer endpoints lacking patched Acrobat or Reader versions.
3

Lateral reach — past segmentation narrative 3

Attacker
When the PDF is opened, the double free vulnerability corrupts heap memory, allowing me to achieve code execution.
Business
Attacker gains arbitrary code execution with the privileges of the user running the PDF reader.
4

Data at risk — exfiltration narrative 4

Attacker
I execute malware, steal data, or establish persistence on the compromised system.
Business
Organization faces data breach, system compromise, or lateral movement into the network.
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)
  • 2 reported-exploitation source(s)
  • CVSS 8.8 — CISA-assigned (CVE.org ADP)
  • CISA SSVC triage disposition (CVE.org ADP)
  • CWE weakness mapping (NVD feed — CNA left none)
  • Catalogued by adobe (CNA)
  • 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.
  • No finder/reporter credit recorded in the public CVE entry — the work behind this find is unattributed.
  • Disclosure & credit2
    Catalogued by adobeCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.