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Threats / Trimble / CVE-2025-0994
CVE-2025-0994 · EUVD no mirror located · GCVE no mirror located Verified 2026-08-04

Trimble Cityworks vulnerability

Trimble Cityworks contains a deserialization vulnerability (CWE-502) that allows authenticated users to execute arbitrary code on IIS web servers.

Verdict

Today item — known-exploited.

An authenticated attacker can exploit unsafe deserialization in Cityworks to achieve remote code execution on the hosting IIS server. Active exploitation in the wild increases operational risk for deployed instances.

CISA KEV Yes · 2025-02-075EPSS 0.31309 (verify live)6CVSS 8.63CISA SSVC Exploitation: active · Automatable: no · Impact: total4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
14 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 2025-02-07).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.31309 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
CVSS 8.6 (CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N) · Affected: Trimble, Cityworks. 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: 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 1 day 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.
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 authenticate to the Cityworks application using valid credentials.
Business
Legitimate user accounts or compromised credentials provide initial access vector to the application.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I craft a malicious serialized object and submit it through the application interface.
Business
The application processes untrusted serialized data without proper validation or integrity checks.
3

Lateral reach — past segmentation narrative 3

Attacker
I trigger deserialization of the malicious payload, causing arbitrary code execution on the IIS server.
Business
The web server executes attacker-controlled code with the privileges of the application service account.
4

Data at risk — exfiltration narrative 4

Attacker
I establish persistence and move laterally within the network infrastructure.
Business
Compromise of the IIS server enables data theft, system manipulation, and potential lateral movement to connected systems.
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)
  • 14 reported-exploitation source(s)
  • CVSS 8.6 — CNA-assigned (CVE.org)
  • CISA SSVC triage disposition (CVE.org ADP)
  • CWE weakness mapping — CNA-assigned (CVE.org)
  • Catalogued by icscert (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 icscertCNA
    Credited with finding itTrimblereporter