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Threats / MongoDB / CVE-2025-14847
CVE-2025-14847 · EUVD no mirror located · GCVE no mirror located Verified 2026-08-04

MongoDB and Server vulnerability

MongoDB Server improperly handles length parameters in Zlib compressed protocol headers, allowing unauthenticated clients to read uninitialized heap memory.

Verdict

Today item — known-exploited.

An unauthenticated attacker can exploit improper length parameter validation in MongoDB's Zlib compression handling to leak sensitive heap memory contents without authentication, potentially exposing credentials or other sensitive data.

CISA KEV Yes · 2025-12-295EPSS 0.83007 (verify live)6Exploit Weaponized · public PoC7CVSS 8.73CISA SSVC Exploitation: active · Automatable: yes · Impact: partial4
01

Is it exploitable?

— the evidence, ranked above the score
Exploit available
Fully weaponized — public exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
10 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 2025-12-29).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.83007 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
CVSS 8.7 (CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N) · Affected: MongoDB, MongoDB and MongoDB Server. 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-130 CWE-130.CWE — CNA-assigned (CVE.org); the weakness class drives how the flaw is exploited.
CVE.org ↗Reported
CISA SSVC (triage disposition)
Exploitation: active · Automatable: yes · Technical Impact: partialCISA'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 10 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 public proof-of-concept / detection template). Catalog entries: Metasploit module, nuclei template. 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 malformed Zlib compressed protocol header with inconsistent length parameters to trigger heap memory read operations.
Business
Sensitive data including credentials, encryption keys, or user information stored in heap memory becomes accessible to unauthenticated attackers.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I repeatedly send crafted requests to extract uninitialized heap memory and reconstruct sensitive information across multiple responses.
Business
Confidentiality of customer data and internal secrets is compromised, creating regulatory compliance violations and reputational damage.
3

Lateral reach — past segmentation narrative 3

Attacker
I use leaked memory contents to identify running software versions, internal structures, or authentication tokens for further exploitation.
Business
Attack surface expands as leaked information enables lateral movement and privilege escalation within the infrastructure.
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)
  • Weaponized exploit available (VulnCheck)
  • 10 reported-exploitation source(s)
  • CVSS 8.7 — CNA-assigned (CVE.org)
  • CISA SSVC triage disposition (CVE.org ADP)
  • CWE weakness mapping — CNA-assigned (CVE.org)
  • Public exploit availability
  • Catalogued by mongodb (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 mongodbCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.