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Threats / Palo Alto Networks / CVE-2024-3393
CVE-2024-3393 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Palo Alto Networks PAN-OS vulnerability

Palo Alto Networks PAN-OS DNS Security feature contains a parsing vulnerability allowing unauthenticated remote attackers to reboot firewalls via malicious DNS packets, potentially forcing maintenance mode through repeated exploitation.

Verdict

Today item — known-exploited.

An unauthenticated attacker can craft malicious DNS packets to trigger a denial-of-service condition in PAN-OS firewalls. Repeated exploitation forces the device into maintenance mode, disrupting network security operations and requiring manual intervention to restore service.

CISA KEV Yes · 2024-12-303EPSS 0.26636 (verify live)4Exploit Public PoC5
01

Is it exploitable?

— the evidence, ranked above the score
Exploit available
Public proof-of-concept exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
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 2024-12-30).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.26636 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Palo Alto Networks, PAN-OS. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-754 Improper Check for Unusual Conditions.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
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 and send malicious DNS packets to the target firewall's DNS Security feature.
Business
Network security infrastructure becomes unavailable, blocking legitimate traffic inspection and policy enforcement.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I trigger the parsing vulnerability to cause an unhandled exception that reboots the firewall.
Business
Security operations lose visibility and control over network traffic during the reboot window.
3

Lateral reach — past segmentation narrative 3

Attacker
I repeat the attack multiple times to force the firewall into maintenance mode.
Business
The firewall requires manual administrative intervention to recover, extending downtime and increasing operational costs.
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)
  • Public PoC available (VulnCheck)
  • 2 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Public exploit availability
  • Catalogued by palo_alto (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