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Full vulnerability report · 2020
CVE-2020-13987High confidence

An Out-of-Bounds Read vulnerability exists in the uIP TCP/IP Stack component when calculating the checksums for IP packets in upper_layer_chksum in net/ipv4/uip.c

n/a · n/a

7.5HighCVSS 3.1
Recommended action
Within 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

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
SSA-541018 · CSAF 2.0 · revision 6 · finalSiemens ProductCERTSSA-541018: Embedded TCP/IP Stack Vulnerabilities (AMNESIA:33) in SENTRON PAC / 3VA Devices (Part 2)
3 known affected

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

  • SENTRON 3VA COM100/800
  • SENTRON PAC3200
  • SENTRON PAC4200
Summary
The TCP/IP stack (uIP) in affected devices is vulnerable to out-of-bounds read when calculating the checksum for IP packets. (FSCT-2020-0009) An attacker located in the same network could trigger a Denial-of-Service condition on the device by sending a specially crafted IP packet.
Remediation
Update to V4.4.1 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.

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-2020-6157

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 actionWithin 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
01

What, why and how

An issue was discovered in Contiki through 3.0. An Out-of-Bounds Read vulnerability exists in the uIP TCP/IP Stack component when calculating the checksums for IP packets in upper_layer_chksum in net/ipv4/uip.c.

What

An issue was discovered in Contiki through 3.0. An Out-of-Bounds Read vulnerability exists in the uIP TCP/IP Stack component when calculating the checksums for IP packets in upper_layer_chksum in net/ipv4/uip.c.

Why

The product reads data past the end, or before the beginning, of the intended buffer.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

An issue was discovered in Contiki through 3.0. An Out-of-Bounds Read vulnerability exists in the uIP TCP/IP Stack component when calculating the checksums for IP packets in upper_layer_chksum in net/ipv4/uip.c.

Why

The product reads data past the end, or before the beginning, of the intended buffer.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

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 → Out-of-bounds Read → cause the confidentiality, integrity or availability impact described by the vendor
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-125 ↗

CWE-125: Out-of-bounds Read. The product reads data past the end, or before the beginning, of the intended buffer.

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.
NetworkUnauthenticatedCWE-125
A

Official authority intelligence

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

BSI · German · WID-SEC-W-2022-1044TCP/IP Stack: Mehrere Schwachstellen

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in TCP/IP Stack ausnutzen, um beliebigen Programmcode mit Administratorrechten auszuführen, einen Denial of Service Angriff durchzuführen, vertrauliche Daten einzusehen oder Daten zu manipulieren.

Official advisory
CERT-FR · French · CERTFR-2022-AVI-124Multiples vulnérabilités dans les produits Siemens

ERecord?id=CVE-2019-13946 Référence CVE CVE-2019-19300 https://www.cve.org/CVERecord?id=CVE-2019-19300 Référence CVE CVE-2019-19301 https://www.cve.org/CVERecord?id=CVE-2019-19301 Référence CVE CVE-2019-6568 https://www.cve.org/CVERecord?id=CVE-2019-6568 Référence CVE CVE-2019-6575 https://www.cve.org/CVERecord?id=CVE-2019-6575 Référence CVE CVE-2019-8460 https://www.cve.org/CVERecord?id=CVE-2019-8460 Référence CVE CVE-2020-12357 https://www.cve.org/CVERecord?id=CVE-2020-12357 Référence CVE CVE-2020-12358 https://www.cve.org/CVERecord?id=CVE-2020-12358 Référence CVE CVE-2020-12360 https://www.cve.org/CVERecord?id=CVE-2020-12360 Référence CVE CVE-2020-13987 https://www.cve.org/CVERecord?id=CVE-2020-13987 Référence CVE CVE-2020-17437 https://www.cve.org/CVERecord?id=CVE-2020-17437 Référence CVE CVE-2020-24486 https://www.cve.org/CVERecord?id=CVE-2020-24486 Référence CVE CVE-2020-24506 https://www.cve.org/CVERecord?id=CVE-2020-24506 Référence CVE CVE-2020-24507 https://www.cve.org/CVERecord?id=CVE-2020-24507 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-2020-24588 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2021-AVI-772Multiples vulnérabilités dans les produits Schneider

ve.org/CVERecord?id=CVE-2019-1040 Référence CVE CVE-2019-11135 https://www.cve.org/CVERecord?id=CVE-2019-11135 Référence CVE CVE-2020-0601 https://www.cve.org/CVERecord?id=CVE-2020-0601 Référence CVE CVE-2020-0609 https://www.cve.org/CVERecord?id=CVE-2020-0609 Référence CVE CVE-2020-0610 https://www.cve.org/CVERecord?id=CVE-2020-0610 Référence CVE CVE-2020-0796 https://www.cve.org/CVERecord?id=CVE-2020-0796 Référence CVE CVE-2020-0938 https://www.cve.org/CVERecord?id=CVE-2020-0938 Référence CVE CVE-2020-1020 https://www.cve.org/CVERecord?id=CVE-2020-1020 Référence CVE CVE-2020-1350 https://www.cve.org/CVERecord?id=CVE-2020-1350 Référence CVE CVE-2020-13987 https://www.cve.org/CVERecord?id=CVE-2020-13987 Référence CVE CVE-2020-1472 https://www.cve.org/CVERecord?id=CVE-2020-1472 Référence CVE CVE-2020-17438 https://www.cve.org/CVERecord?id=CVE-2020-17438 Référence CVE CVE-2021-22800 https://www.cve.org/CVERecord?id=CVE-2021-22800 Référence CVE CVE-2021-22801 https://www.cve.org/CVERecord?id=CVE-2021-22801 Référence CVE CVE-2021-22802 https://www.cve.org/CVERecord?id=CVE-2021-22802 Référence CVE CVE-2021-22803 https://www.cve.org/CVERecord?id=CVE-2021-22803 Référence CVE CVE-2021-22804 https://www.cve.org/CVERecord?id=CVE-2021-22804 Référence CVE CVE-2021-22805 https://www.cve.org/CVERecord?id=CV

Official advisory
CERT-FR · French · CERTFR-2021-AVI-176Multiples vulnérabilités dans les produits Siemens

portal.siemens.com/productcert/pdf/ssa-816980.pdf Bulletin de sécurité Siemens ssa-917115 du 09 mars 2021 https://cert-portal.siemens.com/productcert/pdf/ssa-917115.pdf Bulletin de sécurité Siemens ssa-936080 du 09 mars 2021 https://cert-portal.siemens.com/productcert/pdf/ssa-936080.pdf Bulletin de sécurité Siemens ssa-979775 du 09 mars 2021 https://cert-portal.siemens.com/productcert/pdf/ssa-979775.pdf Référence CVE CVE-2019-10925 https://www.cve.org/CVERecord?id=CVE-2019-10925 Référence CVE CVE-2019-10926 https://www.cve.org/CVERecord?id=CVE-2019-10926 Référence CVE CVE-2019-3823 https://www.cve.org/CVERecord?id=CVE-2019-3823 Référence CVE CVE-2020-13987 https://www.cve.org/CVERecord?id=CVE-2020-13987 Référence CVE CVE-2020-17437 https://www.cve.org/CVERecord?id=CVE-2020-17437 Référence CVE CVE-2020-25236 https://www.cve.org/CVERecord?id=CVE-2020-25236 Référence CVE CVE-2020-25239 https://www.cve.org/CVERecord?id=CVE-2020-25239 Référence CVE CVE-2020-25240 https://www.cve.org/CVERecord?id=CVE-2020-25240 Référence CVE CVE-2020-25241 https://www.cve.org/CVERecord?id=CVE-2020-25241 Référence CVE CVE-2020-27632 https://www.cve.org/CVERecord?id=CVE-2020-27632 Référence CVE CVE-2020-28385 https://www.cve.org/CVERecord?id=CVE-2020-28385 Référence CVE CVE-2020-28387 https://www.cve.org/CVERecord?id=

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
SENTRON 3VA COM100/800; SENTRON PAC3200; SENTRON PAC4200
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
Update to V4.4.1 or later version
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 11 Dec 2020 · Last source change 4 Aug 2024, 12:32 UTC · CWE-125 · Out-of-bounds Read

CVE recordCVE.org · 5.1
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-2020-6157
Product sourceVendor CSAF · Siemens ProductCERT
Remediation sourceVendor CSAF · Siemens ProductCERT
CWE sourceNIST NVD
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 →

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

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-2020-6157↗Patch or update reference↗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-2020-13987 · cve.blacktree.nl