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Full vulnerability report · 2021
CVE-2020-7929High confidence

Specially crafted regex query can cause DoS

MongoDB Inc. · MongoDB Server

6.5MediumCVSS 3.1
Recommended action
Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current
9AKK108472A9037 · CSAF 2.0 · revision 1 · finalABB Product Security Incident Response Team (PSIRT)ABB AbilityTM zenon Security Risk Due to End-of-Life MongoDB Component
1 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • IIoT services with MongoDB 4.2 installed on ABB Ability Zenon /all
Summary
A user authorized to perform database queries may trigger denial of service by issuing specially crafted query contain a type of regex. This issue affects MongoDB Server v3.6 versions prior to 3.6.21 and MongoDB Server v4.0 versions prior to 4.0.20.
Remediation
ABB recommends the following mitigation measures: - Replace bundled MongoDB with a supported version if IIoT services are required: - Where IIoT functionality is required, the bundled MongoDB instance can be replaced with a supported and patched version through manual configuration. - The following zenon online help section explains the process of installing and using your own MongoDB database: zenHelpViewer - Uninstall IIoT Services wherever it’s not required: - If IIoT Services are not required, they can be removed using the Control panel uninstaller. This eliminates the dependency on MongoDB without affecting other zenon components. Refer to section “General security recommendations” for further advise on how to keep your system secure.
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2020-28859

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
01

What, why and how

A user authorized to perform database queries may trigger denial of service by issuing specially crafted query contain a type of regex. This issue affects MongoDB Server v3.6 versions prior to 3.6.21 and MongoDB Server v4.0 versions prior to 4.0.20.

What

A user authorized to perform database queries may trigger denial of service by issuing specially crafted query contain a type of regex. This issue affects MongoDB Server v3.6 versions prior to 3.6.21 and MongoDB Server v4.0 versions prior to 4.0.20.

Why

The product specifies a regular expression in a way that causes data to be improperly matched or compared.

How

An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may disrupt the affected service.

What

A user authorized to perform database queries may trigger denial of service by issuing specially crafted query contain a type of regex. This issue affects MongoDB Server v3.6 versions prior to 3.6.21 and MongoDB Server v4.0 versions prior to 4.0.20.

Why

The product specifies a regular expression in a way that causes data to be improperly matched or compared.

How

An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may disrupt the affected service.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Incorrect Regular Expression → disrupt the affected service
Attack surface
Network
Privileges required
Low: a basic authenticated account is required
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-185 ↗

CWE-185: Incorrect Regular Expression. The product specifies a regular expression in a way that causes data to be improperly matched or compared.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.INoneIntegrity impact: No direct loss is represented by this metric.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkDenial of serviceCWE-185
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

CERT-FR · French · CERTFR-2021-AVI-490Multiples vulnérabilités dans IBM Spectrum Protect

8 juin 2021 https://www.ibm.com/support/pages/node/6466435 Bulletin de sécurité IBM 6466599 du 28 juin 2021 https://www.ibm.com/support/pages/node/6466599 Bulletin de sécurité IBM 6467281 du 28 juin 2021 https://www.ibm.com/support/pages/node/6467281 Référence CVE CVE-2020-14147 https://www.cve.org/CVERecord?id=CVE-2020-14147 Référence CVE CVE-2020-26217 https://www.cve.org/CVERecord?id=CVE-2020-26217 Référence CVE CVE-2020-26258 https://www.cve.org/CVERecord?id=CVE-2020-26258 Référence CVE CVE-2020-26259 https://www.cve.org/CVERecord?id=CVE-2020-26259 Référence CVE CVE-2020-28476 https://www.cve.org/CVERecord?id=CVE-2020-28476 Référence CVE CVE-2020-7929 https://www.cve.org/CVERecord?id=CVE-2020-7929 Référence CVE CVE-2021-21284 https://www.cve.org/CVERecord?id=CVE-2021-21284 Référence CVE CVE-2021-21285 https://www.cve.org/CVERecord?id=CVE-2021-21285 Référence CVE CVE-2021-21341 https://www.cve.org/CVERecord?id=CVE-2021-21341 Référence CVE CVE-2021-21342 https://www.cve.org/CVERecord?id=CVE-2021-21342 Référence CVE CVE-2021-21343 https://www.cve.org/CVERecord?id=CVE-2021-21343 Référence CVE CVE-2021-21344 https://www.cve.org/CVERecord?id=CVE-2021-21344 Référence CVE CVE-2021-21345 https://www.cve.org/CVERecord?id=CVE-2021-21345 Référence CVE CVE-2021-21346 https://www.cve.org/CVERecord?id=C

Official advisory
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
IIoT services with MongoDB 4.2 installed on ABB Ability Zenon /all
Fixed
An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
ABB recommends the following mitigation measures: - Replace bundled MongoDB with a supported version if IIoT services are required: - Where IIoT functionality is required, the bundled MongoDB instance can be replaced with a supported and patched version through manual configuration. - The following zenon online help section explains the process of installing and using your own MongoDB database: zenHelpViewer - Uninstall IIoT Services wherever it’s not required: - If IIoT Services are not required, they can be removed using the Control panel uninstaller. This eliminates the dependency on MongoDB without affecting other zenon components. Refer to section “General security recommendations” for further advise on how to keep your system secure.
04

Evidence and provenance

Published 1 Mar 2021 · Last source change 16 Sept 2024, 19:46 UTC · CWE-185 · Incorrect Regular Expression

CVE recordCVE.org · 5.1
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2020-28859
Product sourceVendor CSAF · ABB Product Security Incident Response Team (PSIRT)
Remediation sourceVendor CSAF · ABB Product Security Incident Response Team (PSIRT)
CWE sourceCNA
NVD statusNVD modified after enrichment

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates →
  1. Vendor guidanceAuthoritative vendor guidance changed from authoritative remediation link to authoritative remediation link.
    Before
    authoritative remediation link
    After
    authoritative remediation link
    ABB Product Security Incident Response Team (PSIRT) ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2020-28859↗Vendor CSAF · ABB Product Security Incident Response Team (PSIRT)↗CVE authority or vendor reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2020-7929 · cve.blacktree.nl