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Full vulnerability report · 2021
CVE-2020-27827High confidence

A flaw was found in multiple versions of OpenvSwitch

Unknown · lldp/openvswitch

7.5HighCVSS 3.1
Recommended action
Patch only the product branches with a verified fix

High technical severity; prioritise exposed affected systems while verifying vendor guidance. Verified remediation exists for at least one product or source, but 17 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityHighOperational priority:High, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
  • EPSS is 3.23% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict the affected network interface to trusted sources where business-safe.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs Unknown lldp/openvswitch and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: Within 30 daysRemediation target: Within 180 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Cross-source reconciliation

Remediation availability differs by product scope

Verified remediation exists for at least one product or source, but 17 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Distribution package intelligence

Release-specific package status

Alpine, Debian, ubuntu findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.

15 package states
Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Distribution releaseSource packageVendor stateFixed versionEvidence
Alpine v3.23v3.23 · communitylldpdVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.1.0.8-r0Alpine Security Database ↗Source updated 11 Sep 2026
Alpine v3.23v3.23 · communityopenvswitchVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.2.12.2-r0Alpine Security Database ↗Source updated 11 Sep 2026
Alpine v3.22v3.22 · communitylldpdVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.1.0.8-r0Alpine Security Database ↗Source updated 11 Sep 2026
Alpine v3.22v3.22 · communityopenvswitchVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.2.12.2-r0Alpine Security Database ↗Source updated 11 Sep 2026
Alpine v3.21v3.21 · communitylldpdVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.1.0.8-r0Alpine Security Database ↗Source updated 19 Aug 2026
Alpine v3.21v3.21 · communityopenvswitchVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.2.12.2-r0Alpine Security Database ↗Source updated 19 Aug 2026
Debian trixietrixie · sourcelldpdVendor fix publishedDebian records a fixed source-package version for this release.1.0.8-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian trixietrixie · sourceopenvswitchVendor fix publishedDebian records a fixed source-package version for this release.2.15.0~git20210104.def6eb1ea+dfsg1-4Debian Security Tracker ↗Source updated 5 Oct 2026
Debian bookwormbookworm · sourcelldpdVendor fix publishedDebian records a fixed source-package version for this release.1.0.8-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian bookwormbookworm · sourceopenvswitchVendor fix publishedDebian records a fixed source-package version for this release.2.15.0~git20210104.def6eb1ea+dfsg1-4Debian Security Tracker ↗Source updated 5 Oct 2026
Debian forkyforky · sourcelldpdVendor fix publishedDebian records a fixed source-package version for this release.1.0.8-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian forkyforky · sourceopenvswitchVendor fix publishedDebian records a fixed source-package version for this release.2.15.0~git20210104.def6eb1ea+dfsg1-4Debian Security Tracker ↗Source updated 5 Oct 2026
Debian sidsid · sourcelldpdVendor fix publishedDebian records a fixed source-package version for this release.1.0.8-1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian sidsid · sourceopenvswitchVendor fix publishedDebian records a fixed source-package version for this release.2.15.0~git20210104.def6eb1ea+dfsg1-4Debian Security Tracker ↗Source updated 5 Oct 2026
Ubuntu 24.04 LTSnoble · standard archivelldpdUnder evaluationCanonical reports that the package might be affected and still needs evaluation or fixing.Not published in this feedCanonical Ubuntu Security ↗Source updated 5 Oct 2026
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
SSA-941426 · CSAF 2.0 · revision 5 · interimSiemens ProductCERTSSA-941426: Multiple LLDP Vulnerabilities in Industrial Products
17 known affected

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

  • SIMATIC CP 1243-1 (6GK7243-1BX30-0XE0)
  • SIMATIC CP 1243-8 IRC (6GK7243-8RX30-0XE0)
  • SIMATIC CP 1542SP-1 (6GK7542-6UX00-0XE0)
  • SIMATIC CP 1542SP-1 IRC (6GK7542-6VX00-0XE0)
  • SIMATIC CP 1543-1 (6GK7543-1AX00-0XE0)
  • SIMATIC CP 1543SP-1 (6GK7543-6WX00-0XE0)
  • SIMATIC CP 1545-1 (6GK7545-1GX00-0XE0)
  • SIMATIC HMI Unified Comfort Panels
  • SINUMERIK ONE MCP
  • SIPLUS ET 200SP CP 1542SP-1 IRC TX RAIL (6AG2542-6VX00-4XE0)
  • SIPLUS ET 200SP CP 1543SP-1 ISEC (6AG1543-6WX00-7XE0)
  • SIPLUS ET 200SP CP 1543SP-1 ISEC TX RAIL (6AG2543-6WX00-4XE0)
Summary
Specially crafted LLDP packets can cause memory to be lost when allocating data to handle specific optional TLVs, potentially causing a denial of service.
Remediation
Update to V2.2.28 or later version
Optional official sources

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

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

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-2020-20326

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 actionPatch only the product branches with a verified fix

High technical severity; prioritise exposed affected systems while verifying vendor guidance. Verified remediation exists for at least one product or source, but 17 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.

Fix availability varies by product
01

What, why and how

A flaw was found in multiple versions of OpenvSwitch. Specially crafted LLDP packets can cause memory to be lost when allocating data to handle specific optional TLVs, potentially causing a denial of service. The highest threat from this vulnerability is to system availability.

What

A flaw was found in multiple versions of OpenvSwitch. Specially crafted LLDP packets can cause memory to be lost when allocating data to handle specific optional TLVs, potentially causing a denial of service. The highest threat from this vulnerability is to system availability.

Why

The product does not properly control the allocation and maintenance of a limited resource.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may disrupt the affected service.

What

A flaw was found in multiple versions of OpenvSwitch. Specially crafted LLDP packets can cause memory to be lost when allocating data to handle specific optional TLVs, potentially causing a denial of service. The highest threat from this vulnerability is to system availability.

Why

The product does not properly control the allocation and maintenance of a limited resource.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. 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 → Uncontrolled Resource Consumption → disrupt the affected service
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
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-400 ↗

CWE-400: Uncontrolled Resource Consumption. The product does not properly control the allocation and maintenance of a limited resource.

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:N/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.PRNonePrivileges required: The attacker does not need an account or existing 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.
NetworkUnauthenticatedDenial of serviceCWE-400
A

Official authority intelligence

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

BSI · German · WID-SEC-2023-0916Red Hat Enterprise Linux: Mehrere Schwachstellen ermöglichen Denial of Service

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Red Hat Enterprise Linux und SUSE Linux ausnutzen, um einen Denial of Service Angriff durchzuführen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20210324Security Bulletin 24 Mar 2021

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 24 Mar 2021, published on 24 March 2021. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2023-AVI-0051Multiples vulnérabilités dans les produits Juniper

rd?id=CVE-2020-1971 Référence CVE CVE-2020-24489 https://www.cve.org/CVERecord?id=CVE-2020-24489 Référence CVE CVE-2020-24511 https://www.cve.org/CVERecord?id=CVE-2020-24511 Référence CVE CVE-2020-24512 https://www.cve.org/CVERecord?id=CVE-2020-24512 Référence CVE CVE-2020-24513 https://www.cve.org/CVERecord?id=CVE-2020-24513 Référence CVE CVE-2020-25704 https://www.cve.org/CVERecord?id=CVE-2020-25704 Référence CVE CVE-2020-26116 https://www.cve.org/CVERecord?id=CVE-2020-26116 Référence CVE CVE-2020-26137 https://www.cve.org/CVERecord?id=CVE-2020-26137 Référence CVE CVE-2020-27170 https://www.cve.org/CVERecord?id=CVE-2020-27170 Référence CVE CVE-2020-27827 https://www.cve.org/CVERecord?id=CVE-2020-27827 Référence CVE CVE-2020-28196 https://www.cve.org/CVERecord?id=CVE-2020-28196 Référence CVE CVE-2020-28469 https://www.cve.org/CVERecord?id=CVE-2020-28469 Référence CVE CVE-2020-35498 https://www.cve.org/CVERecord?id=CVE-2020-35498 Référence CVE CVE-2020-36322 https://www.cve.org/CVERecord?id=CVE-2020-36322 Référence CVE CVE-2020-36385 https://www.cve.org/CVERecord?id=CVE-2020-36385 Référence CVE CVE-2020-8648 https://www.cve.org/CVERecord?id=CVE-2020-8648 Référence CVE CVE-2020-8695 https://www.cve.org/CVERecord?id=CVE-2020-8695 Référence CVE CVE-2020-8696 https://www.cve.org/CVERecord?id=CVE-2

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-518Multiples vulnérabilités dans les produits Siemens

emens.com/productcert/pdf/ssa-729965.pdf Bulletin de sécurité Siemens ssa-772220 du 13 juillet 2021 https://cert-portal.siemens.com/productcert/pdf/ssa-772220.pdf Bulletin de sécurité Siemens ssa-913875 du 13 juillet 2021 https://cert-portal.siemens.com/productcert/pdf/ssa-913875.pdf Bulletin de sécurité Siemens ssa-941426 du 13 juillet 2021 https://cert-portal.siemens.com/productcert/pdf/ssa-941426.pdf Référence CVE CVE-2015-8011 https://www.cve.org/CVERecord?id=CVE-2015-8011 Référence CVE CVE-2020-15782 https://www.cve.org/CVERecord?id=CVE-2020-15782 Référence CVE CVE-2020-26147 https://www.cve.org/CVERecord?id=CVE-2020-26147 Référence CVE CVE-2020-27827 https://www.cve.org/CVERecord?id=CVE-2020-27827 Référence CVE CVE-2020-28400 https://www.cve.org/CVERecord?id=CVE-2020-28400 Référence CVE CVE-2021-20093 https://www.cve.org/CVERecord?id=CVE-2021-20093 Référence CVE CVE-2021-20094 https://www.cve.org/CVERecord?id=CVE-2021-20094 Référence CVE CVE-2021-25671 https://www.cve.org/CVERecord?id=CVE-2021-25671 Référence CVE CVE-2021-29998 https://www.cve.org/CVERecord?id=CVE-2021-29998 Référence CVE CVE-2021-31892 https://www.cve.org/CVERecord?id=CVE-2021-31892 Référence CVE CVE-2021-31893 https://www.cve.org/CVERecord?id=CVE-2021-31893 Référence CVE CVE-2021-31894 https://www.cve.org/CVERecord?id=

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2020-016396Open vSwitch におけるリソースの枯渇に関する脆弱性

Open vSwitch には、リソースの枯渇に関する脆弱性が存在します。

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.
Fix availability varies by product
Affected
Fixed
Update to V2.2.28 or later version
Action
Use the product-specific evidence above. Patch only products with a verified fixed release, and keep every affected or under-investigation state without a matching fix in the remediation queue.
Workaround
A mitigation or workaround reference is available from the source linked below; validate it against the affected product and version.
04

Evidence and provenance

Published 18 Mar 2021 · Last source change 3 Dec 2025, 18:20 UTC · CWE-400 · Uncontrolled Resource Consumption

CVE recordCVE.org · 5.2
CVSS sourceNIST NVD
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-2020-20326
Product sourceVendor CSAF · Siemens ProductCERT
Remediation sourceVendor CSAF · Siemens ProductCERT
CWE sourceCNA
NVD statusNVD modified after enrichment

Missing structured fields: affected product. Missing data is not evidence of low risk; review the primary advisory.

Material change intelligence

What changed after publication

View recent updates ↗
  1. Affected versionsThe structured affected or fixed version information changed.
    Before
    lldpd 1.0.8, openvswitch 2.14.1, openvswitch 2.13.2, openvswitch 2.12.2, openvswitch 2.11.5, openvswitch 2.10.6, openvswitch 2.9.8, openvswitch 2.8.10, openvswitch 2.7.12, openvswitch 2.6.9 · 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.
    After
    lldpd 1.0.8, openvswitch 2.14.1, openvswitch 2.13.2, openvswitch 2.12.2, openvswitch 2.11.5, openvswitch 2.10.6, openvswitch 2.9.8, openvswitch 2.8.10, openvswitch 2.7.12, openvswitch 2.6.9 · Fixed: Update to V2.2.28 or later version
    Siemens ProductCERT ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
Fixed release recorded from official guidance
ENISA EUVD · EUVD-2020-20326↗Patch or update reference↗CVE authority or vendor reference↗Mitigation 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-2020-27827 · cve.blacktree.nl