What is CVE-2025-14847?

CVE-2025-14847 is Zlib compressed protocol header length confusion may allow memory read. The supplied enrichment data classifies it as Unclassified mapped to CWE-130 CWE-130.

Which versions are affected?

Affected product and version evidence is listed in the product table above. Current public advisories should be checked for exact version scope before patch targeting is finalized.

Is there active exploitation?

Yes: CISA KEV signal present. If exploitation is not confirmed from current sources, teams should document that status and continue monitoring KEV, vendor, and telemetry updates.

Is there a public exploit?

69 public PoC repositories reported; 2 marked weaponized in current dataset. Public exploit or PoC availability should raise triage priority, especially for exposed or business-critical systems.

How can defenders detect it?

Start with web/proxy/WAF logs, application logs, network IDS/IPS where available. Look for vulnerability-class behavior, product errors, suspicious authentication events, exploit probes, and abnormal process activity based only on evidence that applies to the affected product.

How should teams prioritize it?

Prioritize CVE-2025-14847 using CVSS 7.5, EPSS 83%, KEV status, public PoC status, and asset exposure. Internet-facing, privileged, or business-critical deployments should be handled first.

Are workarounds available?

The supplied mitigation guidance says to apply vendor patches and restrict external exposure until fixed. Fixed-version evidence is listed in the mitigation section above.

Which threat actors are linked publicly?

Publicly linked actor or ransomware signals in the supplied enrichment data: UNC215 (), BRONZE SPRING (), TA428 (), Iron Group (), APT-C-27 (). Do not attribute exploitation to a threat actor unless the source evidence explicitly supports that linkage.

What should be done in the next 24 hours?

Identify exposed assets running affected vendor/product/version combinations. Treat as emergency remediation because CISA KEV status is present. Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class. Open remediation tickets with affected assets, owners, evidence status, and detection coverage so decisions are traceable.

CISA KEVhighpublic exploit

CVE-2025-14847

CVE-2025-14847 — Zlib compressed protocol header length confusion may allow memory read

Q: Is it in CISA KEV?

Yes. The supplied enrichment data lists CVE-2025-14847 in CISA KEV with required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.. KEV status should be monitored because it can change after initial disclosure or after exploitation becomes publicly confirmed.

Mismatched length fields in Zlib compressed protocol headers may allow a read of uninitialized heap memory by an unauthenticated client. This issue affects all MongoDB Server v7.0 prior to 7.0.28 versions, MongoDB Server v8.0 versions prior to 8.0.17, MongoDB Server v8.2 versions prior to 8.2.3, MongoDB Server v6.0 versions prior to 6.0.27, MongoDB Server v5.0 versions prior to 5.0.32, MongoDB Server v4.4 versions prior to 4.4.30, MongoDB Server v4.2 versions greater than or equal to 4.2.0, MongoDB Server v4.0 versions greater than or equal to 4.0.0, and MongoDB Server v3.6 versions greater than or equal to 3.6.0.

Published Dec 19, 2025Updated Jun 17, 2026Sources: NVD, MongoDB Inc. (CNA), CISA, FIRST EPSS, SOCRadar CTI

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.

Exploitation

Confirmed

CISA KEV, listed Dec 29, 2025

EPSS

83%

ahead of 99.7% of scored CVEs

Affects

MongoDB Inc.

9 products listed

CVSS base

7.5

high · 2 sources

CISA SSVC assessment

Three decision points CISA publishes for the CVEs it assesses · SSVC 2.0.3. A stakeholder decision, not a severity score.

CISA

Exploitation

Active

none · proof-of-concept · active

Automatable

Yes

can an attacker script all four kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Remediation

The vendor's own words where we have them.

Upgrade MongoDB Server to a fixed release. Apply vendor patches per advisory and restrict external exposure of the affected component until patched.

CISA required action

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Federal deadline Jan 19, 2026 — passed 242 days ago

First 24 hours

Ordered from the record's own fields — exposure first, because you cannot patch what you have not found.

Identify exposed assets running affected vendor/product/version combinations.
Treat as emergency remediation because CISA KEV status is present.
Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class.

Affected scope

Vendor, product and version as the advisories word them.

Vendor	Product	Versions	Status
MongoDB Inc.	MongoDB Server	8.2 to < 8.2.3	Vulnerable
MongoDB Inc.	MongoDB Server	8.0 to < 8.0.17	Vulnerable
MongoDB Inc.	MongoDB Server	7.0 to < 7.0.28	Vulnerable
MongoDB Inc.	MongoDB Server	6.0 to < 6.0.27	Vulnerable
MongoDB Inc.	MongoDB Server	5.0 to < 5.0.32	Vulnerable
MongoDB Inc.	MongoDB Server	4.4 to < 4.4.30	Vulnerable
MongoDB Inc.	MongoDB Server	4.2	Vulnerable
MongoDB Inc.	MongoDB Server	4.0	Vulnerable
MongoDB Inc.	MongoDB Server	3.6	Vulnerable

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Availability

None

Confidentiality

High

Integrity

None

Scope

Unchanged

Attack Complexity

Low

Attack Vector

Network

Privileges Req

None

User Interaction

None

Every base score collected

Sources score independently and disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Source
7.5	CVSS 3.1	high	3.9	3.6	mongodb.com (CNA), MongoDB Inc. (CNA)
8.7	CVSS 4.0	high	—	—	MongoDB Inc. (CNA)

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

What this weakness leads to

MITRE's own consequences and mitigations for the weakness class — the authority's wording, not guidance derived from the CVSS vector.

MITRE

CWE-130 · Improper Handling of Length Parameter Inconsistency

Read Memory
Modify Memory
Varies by Context::

Mitigation: When processing structured incoming data containing a size field followed by raw data, ensure that you identify and resolve any inconsistencies between the size field and the actual size of the data.

Weakness & attack patterns

CWE-130

Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.

CAPEC-47 · Buffer Overflow via Parameter Expansion

CISA KEV details

CISA lists a CVE here once it has evidence of exploitation against real targets.

CISAThat month →

Listed

Dec 29, 2025

Federal deadline

Jan 19, 2026

passed 242 days ago

Ransomware use

Unknown

CISA records ransomware use only for campaigns it has confirmed, so “Unknown” means unrecorded, not ruled out. The deadline binds US federal agencies; for everyone else it is a date to argue against.

Public exploit

Capability, not use: code existing is a different claim from anyone running it.

Repositories

2 of the 5 sampled are weaponized

Exploit entries

Exploit-DB and CTI exploit indexes

Social mentions

Posts naming this CVE. Attention, not evidence of exploitation — it spikes on disclosure and decays whether or not anything is exploited.

35 more posts on this CVEShowing 5 of 40 · Who is discussing this CVE, and how loudlyUnlock free

Detection

Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.

Prioritize edge telemetry for network-reachable MongoDB Server.
Monitor for scanner or exploit-pattern traffic after 69 public PoC repositories were reported.

web/proxy/WAF logsapplication logsnetwork IDS/IPS

Groups associated with this CVE

Groups reported in connection with this vulnerability. A reported association, not a confirmed observation of that group using it — and not scoped to any sector or campaign.

UNC215BRONZE SPRINGTA428Iron GroupAPT-C-27

4 more threat groups on this CVEShowing 5 of 9 · Attribution, campaigns and the malware each one runsUnlock free

ip103.139.59.22654
AbuseIPDB Hourly Update · Feb 26, 2026
ip1.234.27.15943
Rutgers Blacklisted IPs · Feb 23, 2026
ip210.245.84.3960
IPsum · Aug 26, 2024
ip171.244.37.9744
Zonefiles · Nov 18, 2023
ip150.242.14.12975
Blocklist.de Feed · Jan 30, 2021

5 more indicators on this CVEShowing 5 of 10 · Hashes, addresses and domains from a live threat exchangeUnlock free

Timeline

What happened to this CVE, newest first — with the readings a source repeats on a schedule counted underneath rather than listed.

2026
Cve is exploited codeb0ssx/CVE-2025-14847-PoC
Jul 24, 2026 · SOCRadar CTI
Added · CVSS 3.1 7.5 (AV:N)
Jun 17, 2026 · NVD
2025
Added to CISA KEV catalog
Dec 29, 2025 · CISA
Initial · CVE published
Dec 19, 2025 · NVD

Source activity

Readings a source repeats on a schedule, counted rather than listed.

11×TweetsFeb 11, 2026 – Jul 23, 2026 · SOCRadar CTI
11×SVRS was changedFeb 18, 2026 – May 25, 2026 · SOCRadar CTI
5×Github ReposFeb 23, 2026 – Jun 14, 2026 · SOCRadar CTI
2×TelegramFeb 12, 2026 – Feb 26, 2026 · SOCRadar CTI

References

7 on the record

jira.mongodb.org/browse/SERVER-115508
Issue Tracking, Patch, Vendor Advisory, NIST
www.openwall.com/lists/oss-security/2025/12/29/21
Mailing List, NIST, GITHUB
www.smartkeyss.com/post/mongobleed-pre-auth-memory-disclosure-via-op_compressed-in-mongodb-cve-2025-14847
Technical Description, Third Party Advisory, NIST
www.vicarius.io/vsociety/posts/cve-2025-14847-detection-script-heap-memory-exposure-in-mongodb-server
Exploit, Third Party Advisory, NIST, GITHUB
www.vicarius.io/vsociety/posts/cve-2025-14847-mitigation-script-heap-memory-exposure-in-mongodb-server
Exploit, Third Party Advisory, NIST, GITHUB
www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-14847
Third Party Advisory, US Government Resource
nvd.nist.gov/vuln/detail/CVE-2025-14847
Vendor Advisory

Coverage

15 stories from the feeds we poll

10 more reports on this CVEShowing 5 of 15 · Vendor research and security press coverageUnlock free

Elsewhere on this site

MongoDB Inc.every CVE for this vendor
December 2025what else CISA listed
Unclassifiedsame class
CWE-130other pages naming this weakness

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

Only the 5 indicator(s) reported for this CVE are available; no packet-level or host-forensic artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record1

What should defenders know first?

CVE-2025-14847 is Zlib compressed protocol header length confusion may allow memory read, a high vulnerability affecting MongoDB Server from MongoDB Inc.. The current evidence lists it in CISA KEV, and the exploit status is: Yes: CISA KEV signal present. Public exploit evidence is: 69 public PoC repositories reported; 2 marked weaponized in current dataset. The affected-version evidence is listed in the key facts and affected products tables. Defenders should first verify whether exposed or business-critical assets run those versions, then apply vendor patches or mitigations, restrict reachable attack surface, and preserve logs for detection review. CVSS 7.5 describes technical severity, while EPSS 83% helps estimate near-term exploit likelihood; neither replaces asset context. Unknown fields should remain explicit in tickets, and threat actor, IOC, victimology, or payload claims should not be added unless a cited source supports them. Monitor CISA KEV, vendor advisories, NVD changes, public PoC repositories, and internal telemetry for update triggers.