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Threats / Cisco / CVE-2026-20128
CVE-2026-20128 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Cisco Catalyst SD-WAN Manager vulnerability

Cisco Catalyst SD-WAN Manager stores passwords in recoverable format, allowing authenticated local attackers to extract DCA credentials from the filesystem and escalate privileges.

Verdict

Today item — known-exploited.

An authenticated local attacker with low privileges can read a credential file on the filesystem to recover DCA user passwords in plaintext or easily reversible format, enabling privilege escalation to DCA administrative access.

CISA KEV Yes · 2026-04-203EPSS 0.046 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
12 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 2026-04-20).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.046 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Cisco, Catalyst SD-WAN Manager. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-257 CWE-257.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 gain initial access as a low-privileged local user on the SD-WAN Manager system.
Business
An insider or compromised account exists within the organization with local system access.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I locate and read the credential file storing DCA user passwords in recoverable format.
Business
Weak credential storage practices expose sensitive authentication material to local file access.
3

Lateral reach — past segmentation narrative 3

Attacker
I recover the DCA password and authenticate as a DCA administrative user.
Business
Privilege escalation compromises the integrity and availability of SD-WAN infrastructure management.
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)
  • 12 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Catalogued by cisco (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 ciscoCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.