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Threats / Adobe / CVE-2009-3459
CVE-2009-3459 · EUVD no mirror located · GCVE no mirror located Verified 2026-08-04

Adobe Acrobat and Reader vulnerability

Adobe Acrobat and Reader contain a heap-based buffer overflow in PDF processing that allows remote code execution when opening a malicious PDF file.

Verdict

Today item — known-exploited.

A remote attacker can craft a PDF document that triggers memory corruption in Adobe Acrobat or Reader, leading to arbitrary code execution on the victim's system. This vulnerability has been actively exploited in the wild.

CISA KEV Yes · 2026-05-204EPSS 0.86583 (verify live)5CVSS 8.8 (CISA)3CISA SSVC Exploitation: active · Automatable: no · Impact: total3Exploit Weaponized · public exploit · Metasploit module12
01

Is it exploitable?

— the evidence, ranked above the score
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.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2026-05-20).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.86583 — 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-119 Memory Buffer Bounds Error — 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 6063 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.
Public exploit available
Public exploit tooling is catalogued for this CVE (a functional/weaponized public exploit). Catalog entries: Metasploit module. We link the catalog page(s) only — no payload or code is hosted or restated here.Link, never host — the catalog page is the source; basicsecurity.net does not redistribute payloads.
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 file designed to overflow a heap buffer during parsing.
Business
An employee receives the PDF via email or downloads it from a compromised website.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I deliver the PDF to the target through email, web download, or file sharing.
Business
The organization's email and web security controls fail to detect the malicious payload.
3

Lateral reach — past segmentation narrative 3

Attacker
I trigger code execution when the victim opens the PDF in Acrobat or Reader.
Business
Arbitrary code runs with the privileges of the user who opened the file.
4

Data at risk — exfiltration narrative 4

Attacker
I establish persistence and move laterally within the network.
Business
Sensitive data is accessed, exfiltrated, or systems are compromised for further attacks.
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)
  • 3 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.