VulnerabilityPublished 19 Dec 2025Updated 26 Feb 2026

CVE-2025-14847: MongoDB Server · Improper Handling of Length Parameter Inconsistency

Affects MongoDB ServerSource CVE Database V5

Exploited in the wild · KEV due 19 Jan 2026 · public detection template (Nuclei) · 83% EPSS · fixed in 8.2.3 : patch MongoDB Server now.

Data as of 8 Nov 2026, 23:23 UTC

CVSS 4.0 base score

8.7High

How severe the flaw is on the 0–10 CVSS scale.

KEV deadline: 19 Jan 2026 US federal agencies must patch by this date; a sensible deadline for everyone else. Other KEV due dates
EPSS: 83.2% chance of exploitation in 30 days – higher than 99% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 8.2.3, 8.0.17, 7.0.28 +3

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

Attack Vector: Network
Attack Complexity: Low
Attack Requirements: None
Privileges Required: None
User Interaction: None
Vulnerable system confidentiality: High
Vulnerable system integrity: None
Vulnerable system availability: None
Subsequent system confidentiality: None
Subsequent system integrity: None
Subsequent system availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, up to and including the entire Internet. Such a vulnerability is often termed “remotely exploitable” and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Attack Requirements: None: The successful attack does not depend on the deployment and execution conditions of the vulnerable system. The attacker can expect to be able to reach the vulnerability and execute the exploit under all or most instances of the vulnerability.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files of the vulnerable system to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without interaction from any human user, other than the attacker.
Vulnerable system confidentiality: High: There is a total loss of confidentiality, resulting in all information within the Vulnerable System being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact. For example, an attacker steals the administrator's password, or private encryption keys of a web server.
Vulnerable system integrity: None: There is no loss of integrity within the Vulnerable System.
Vulnerable system availability: None: There is no impact to availability within the Vulnerable System.
Subsequent system confidentiality: None: There is no loss of confidentiality within the Subsequent System or all confidentiality impact is constrained to the Vulnerable System.
Subsequent system integrity: None: There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System.
Subsequent system availability: None: There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

t = 0 is the CVE’s publication on cve.org

Disclosed: evidence found.
CVE published 19 Dec 2025
Detectable: evidence found.
nuclei template: MongoDB Server - Information Disclosure (MongoBleed)
Weaponized: no evidence on record.
1 Metasploit scanner module; no exploit code indexed
Exploited in the wildExploited: evidence found.
Listed in CISA KEV 10 days after disclosure
Observed by OffSeq MirageSeen by Mirage: evidence found.
13 exposed hosts found; no attack traffic recorded

CVE ID reserved
by MongoDB, Inc.
17 Dec 202518:56 UTC, 40 hours before disclosure
CVE published
on cve.org
19 Dec 202511:09 UTC, t = 0
In Threat Radar
record ingested
19 Dec 202511:09 UTC, 1 minute after disclosure
Added to CISA KEV (opens in a new tab)
exploitation confirmed
29 Dec 2025, 10 days after disclosure
KEV remediation due
US federal deadline
19 Jan 2026, 31 days after disclosure

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CISA KEV (opens in a new tab), OffSeq Mirage (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 8 Nov 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
MongoDB Inc.MongoDB Server	Affected >=8.2 <8.2.3 >=8.0 <8.0.17 >=7.0 <7.0.28 >=6.0 <6.0.27 >=5.0 <5.0.32 >=4.4 <4.4.30 =4.2 =4.0 =3.6	Fixed in 8.2.3 8.0.17 7.0.28 6.0.27 5.0.32 4.4.30

Description

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.

Impact

The primary impact of this vulnerability is unauthorized disclosure of sensitive information due to reading uninitialized heap memory. Attackers can remotely exploit this flaw without authentication, potentially gaining access to memory contents that may include credentials, configuration data, or other sensitive information. This compromises confidentiality and could facilitate further attacks such as privilege escalation or lateral movement. Given MongoDB's widespread use in enterprise, cloud, and web applications, the vulnerability poses a significant risk to data security globally. Systems running vulnerable MongoDB versions may be targeted by attackers seeking to extract sensitive data or gain insights into internal memory states. The lack of required privileges or user interaction lowers the barrier for exploitation, increasing the likelihood of attacks once exploit code becomes available. Although availability and integrity are not directly impacted, the confidentiality breach alone can have severe consequences including regulatory non-compliance, reputational damage, and financial loss.

Mitigation

Organizations should immediately upgrade MongoDB Server to the fixed versions: 7.0.28 or later, 8.0.17 or later, 8.2.3 or later, 6.0.27 or later, 5.0.32 or later, 4.4.30 or later, or 4.2.0 and above with the latest patches. If you cannot patch yet, restrict network access to MongoDB instances by implementing strict firewall rules and network segmentation to limit exposure to untrusted networks. Employ network intrusion detection and prevention systems to monitor for anomalous or malformed compressed protocol traffic indicative of exploitation attempts. Disable or limit the use of Zlib compression in MongoDB if feasible, to reduce attack surface. Conduct regular memory and log analysis to detect potential information leakage or suspicious activity. Additionally, enforce strong authentication and encryption for MongoDB connections to reduce risk from other attack vectors. Maintain an incident response plan to quickly address any suspected exploitation. Finally, stay informed on MongoDB security advisories for updates or emerging exploit reports.

Metasploit modules

MongoDB Memory Disclosure (CVE-2025-14847) - Mongobleedauxiliary · Normal (opens in a new tab)

Nuclei detection templates

MongoDB Server - Information Disclosure (MongoBleed)high (opens in a new tab)

Public tooling indexed from Metasploit Framework, Exploit-DB, ProjectDiscovery nuclei-templates and PoC-in-GitHub. Its existence raises the odds of exploitation; it does not confirm attacks.

CWE-130Improper Handling of Length Parameter Inconsistency (opens in a new tab)
Base weakness
The product parses a formatted message or structure, but it does not handle or incorrectly handles a length field that is inconsistent with the actual length of the associated data.
Implementation
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.
Implementation
Do not let the user control the size of the buffer.
Implementation
Validate that the length of the user-supplied data is consistent with the buffer size.
OWASP Cheat Sheets
XML Security (opens in a new tab)
Mass Assignment (opens in a new tab)
OWASP ASVS 4.0.3
V13.3.1 (opens in a new tab)
V5.1.4 (opens in a new tab)
V5.1.3 (opens in a new tab)
Attack patterns
Buffer Overflow via Parameter Expansion (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

Timeline

What to do

Affected software

Description

AI analysisMachine-generated, updated 5 Mar 2026, 11:10 UTC

Public exploits and detection1 Metasploit scanner module, a Nuclei detection template

WeaknessesCWE-130

Technical details

References

Community reviews

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