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 91.66% for the current model date.
BlackTreeCVE IntelligenceFull vulnerability report · 2019
CVE-2019-11479High confidence
This allows a remote peer to fragment TCP resend queues significantly more than if a larger MSS were enforced
Linux · Linux kernel
Official source article: Siemens SSA-462066 ↗. Check the applicable product and release in the original source.
7.5HighCVSS 3.1
Patch only the product branches with a verified fix
Fix availability varies by productHigh technical severity; prioritise exposed affected systems while verifying vendor guidance. Verified remediation exists for at least one product or source, but 91 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
R
Open reassessment dashboard →Operational reassessment
Published severity in operational context
Published severityHigh→Operational priority:Critical, raised one band.upgradedsince 5 Oct 2026
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
- Confirm that the asset runs Linux Linux kernel and falls inside the recorded affected range.
- Verify the installed build against the product-specific fixed version after deployment.
- Validate exposure, authentication requirements and compensating controls in the actual environment.
- Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Remediation availability differs by product scope
Verified remediation exists for at least one product or source, but 91 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
- Siemens ProductCERT: 90 affected or under-investigation product states without a fixed product state in the same current advisory
- Canonical Ubuntu Security: 1 affected package state with no published fix
Distribution package intelligence
5 package statesRelease-specific package status
Debian, ubuntu findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.
Package result overrides the generic status
BlackTree has verified remediation for at least one product or source, but the relevant distribution still reports no fixed package for 1 affected package state shown here. Treat those rows as affected with no fix until that distribution publishes a fixed version.
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 release | Source package | Vendor state | Fixed version | Evidence |
|---|---|---|---|---|
| Debian trixietrixie · source | linux | Vendor fix publishedDebian records a fixed source-package version for this release. | 4.19.37-4 | Debian Security Tracker ↗Source updated 5 Oct 2026 |
| Debian bookwormbookworm · source | linux | Vendor fix publishedDebian records a fixed source-package version for this release. | 4.19.37-4 | Debian Security Tracker ↗Source updated 5 Oct 2026 |
| Debian forkyforky · source | linux | Vendor fix publishedDebian records a fixed source-package version for this release. | 4.19.37-4 | Debian Security Tracker ↗Source updated 5 Oct 2026 |
| Debian sidsid · source | linux | Vendor fix publishedDebian records a fixed source-package version for this release. | 4.19.37-4 | Debian Security Tracker ↗Source updated 5 Oct 2026 |
| Ubuntu 24.04 LTSnoble · standard archive | linux-raspi-realtime | Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition. | Not published in this feed | Canonical Ubuntu Security ↗Source updated 5 Oct 2026 |
Direct vendor intelligence
1 currentAuthoritative 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.
SSA-462066 · CSAF 2.0 · revision 22 · interimSiemens ProductCERTSSA-462066: Vulnerability known as TCP SACK PANIC in Industrial Products
The vendor explicitly identifies these products as affected by this CVE.
- RUGGEDCOM APE1404 Linux
- RUGGEDCOM RM1224 family (6GK6108-4AM00)
- RUGGEDCOM ROX II
- RUGGEDCOM RX1400 VPE Debian Linux
- RUGGEDCOM RX1400 VPE Linux CloudConnect
- SCALANCE M804PB (6GK5804-0AP00-2AA2)
- SCALANCE M812-1 ADSL-Router (Annex A) (6GK5812-1AA00-2AA2)
- SCALANCE M812-1 ADSL-Router (Annex B) (6GK5812-1BA00-2AA2)
- SCALANCE M816-1 ADSL-Router (Annex A) (6GK5816-1AA00-2AA2)
- SCALANCE M816-1 ADSL-Router (Annex B) (6GK5816-1BA00-2AA2)
- SCALANCE M826-2 SHDSL-Router (6GK5826-2AB00-2AB2)
- SCALANCE M874-2 (6GK5874-2AA00-2AA2)
- Summary
- An attacker with network access to affected products could cause a denial of service condition because of a vulnerability in the TCP retransmission queue implementation kernel when handling TCP Selective Acknowledgements (SACK).
- Remediation
- Update to V1.1.5 or later version
High technical severity; prioritise exposed affected systems while verifying vendor guidance. Verified remediation exists for at least one product or source, but 91 structured product or package states remain unresolved. Apply remediation only to the exact product branch confirmed by its source.
Fix availability varies by product01
What, why and how
Jonathan Looney discovered that the Linux kernel default MSS is hard-coded to 48 bytes. This allows a remote peer to fragment TCP resend queues significantly more than if a larger MSS were enforced. A remote attacker could use this to cause a denial of service. This has been fixed in stable kernel releases 4.4.182, 4.9.182, 4.14.127, 4.19.52, 5.1.11, and is fixed in commits 967c05aee439e6e5d7d805e195b3a20ef5c433d6 and 5f3e2bf008c2221478101ee72f5cb4654b9fc363.
What
Jonathan Looney discovered that the Linux kernel default MSS is hard-coded to 48 bytes. This allows a remote peer to fragment TCP resend queues significantly more than if a larger MSS were enforced. A remote attacker could use this to cause a denial of service. This has been fixed in stable kernel releases 4.4.182, 4.9.182, 4.14.127, 4.19.52, 5.1.11, and is fixed in commits 967c05aee439e6e5d7d805e195b3a20ef5c433d6 and 5f3e2bf008c2221478101ee72f5cb4654b9fc363.
Why
The product does not properly control situations in which an adversary can cause the product to consume or produce excessive resources without requiring the adversary to invest equivalent work or otherwise prove authorization, i.e., the adversary's influence is asymmetric.
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
Jonathan Looney discovered that the Linux kernel default MSS is hard-coded to 48 bytes. This allows a remote peer to fragment TCP resend queues significantly more than if a larger MSS were enforced. A remote attacker could use this to cause a denial of service. This has been fixed in stable kernel releases 4.4.182, 4.9.182, 4.14.127, 4.19.52, 5.1.11, and is fixed in commits 967c05aee439e6e5d7d805e195b3a20ef5c433d6 and 5f3e2bf008c2221478101ee72f5cb4654b9fc363.
Why
The product does not properly control situations in which an adversary can cause the product to consume or produce excessive resources without requiring the adversary to invest equivalent work or otherwise prove authorization, i.e., the adversary's influence is asymmetric.
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 No confirmed evidence
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.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 None recorded
?
Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.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 → Asymmetric Resource Consumption (Amplification) → 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-405 ↗
CWE-405: Asymmetric Resource Consumption (Amplification). The product does not properly control situations in which an adversary can cause the product to consume or produce excessive resources without requiring the adversary to invest equivalent work or otherwise prove authorization, i.e., the adversary's influence is asymmetric.
- 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:HCommon 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.
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
- RUGGEDCOM APE1404 Linux
- RUGGEDCOM RM1224 family (6GK6108-4AM00)
- RUGGEDCOM ROX II
- RUGGEDCOM RX1400 VPE Debian Linux
- RUGGEDCOM RX1400 VPE Linux CloudConnect
- SCALANCE M804PB (6GK5804-0AP00-2AA2)
- SCALANCE M812-1 ADSL-Router (Annex A) (6GK5812-1AA00-2AA2)
- SCALANCE M812-1 ADSL-Router (Annex B) (6GK5812-1BA00-2AA2)
- SCALANCE M816-1 ADSL-Router (Annex A) (6GK5816-1AA00-2AA2)
- SCALANCE M816-1 ADSL-Router (Annex B) (6GK5816-1BA00-2AA2)
- SCALANCE M826-2 SHDSL-Router (6GK5826-2AB00-2AB2)
- SCALANCE M874-2 (6GK5874-2AA00-2AA2)
- SCALANCE M874-3 (6GK5874-3AA00-2AA2)
- SCALANCE M875
- SCALANCE M876-3 (EVDO) (6GK5876-3AA02-2BA2)
- SCALANCE M876-3 (ROK) (6GK5876-3AA02-2EA2)
- SCALANCE M876-4 (EU) (6GK5876-4AA00-2BA2)
- SCALANCE M876-4 (NAM) (6GK5876-4AA00-2DA2)
- SCALANCE S615 (6GK5615-0AA00-2AA2)
- SCALANCE SC622-2C (6GK5622-2GS00-2AC2)
- SCALANCE SC632-2C (6GK5632-2GS00-2AC2)
- SCALANCE SC636-2C (6GK5636-2GS00-2AC2)
- SCALANCE SC642-2C (6GK5642-2GS00-2AC2)
- SCALANCE SC646-2C (6GK5646-2GS00-2AC2)
- SCALANCE W-1700 IEEE 802.11ac family
- SCALANCE W-700 IEEE 802.11n family
- SCALANCE W1750D
- SCALANCE WLC711
- SCALANCE WLC712
- SIMATIC Cloud Connect 7 CC712 (6GK1411-1AC00)
- and 60 more
- 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 Jun 2019 · Last source change 16 Sept 2024, 23:22 UTC · CWE-405 · Asymmetric Resource Consumption (Amplification)
CVE recordCVE.org · 5.1
CVSS sourceNIST NVD
EPSS source FIRST · tracked since 2026-09-01
?
The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.European sourceENISA EUVD · EUVD-2019-3152
Product sourceVendor CSAF · Siemens ProductCERT
Remediation sourceVendor CSAF · Siemens ProductCERT
CWE sourceCNA
NVD statusNVD modified after enrichment
Core structured fields are present and their contributing authorities are shown above.
Material change intelligence
View recent updates ↗What changed after publication
- ENISA EUVD mappingEUVD-2019-3152 was added to the official ENISA EUVD mapping for this CVE.ENISA EUVD ↗
- Before
- not recorded
- After
- {"euvdId":"EUVD-2019-3152"}
- Vendor guidanceAuthoritative vendor guidance changed: added mitigation: wiki.ubuntu.com/SACKPanic; added patch: git.kernel.org/commit?id=5f3e2bf008c2221478101ee72f5cb4654b9fc363; removed vendor advisory: access.redhat.com/RHSA-2019:1594; removed vendor advisory: access.redhat.com/RHSA-2019:1602; 3 further additions; 3 further removals.github.com ↗
- Before
- vendor advisory: access.redhat.com/RHSA-2019:1594 · vendor advisory: access.redhat.com/RHSA-2019:1602 · vendor advisory: access.redhat.com/RHSA-2019:1699 · 2 more references
- After
- mitigation: wiki.ubuntu.com/SACKPanic · patch: git.kernel.org/commit?id=5f3e2bf008c2221478101ee72f5cb4654b9fc363 · patch: git.kernel.org/commit?id=967c05aee439e6e5d7d805e195b3a20ef5c433d6 · 2 more references
- Affected versionsThe structured affected or fixed version information changed.CNA ↗
- Before
- 4.4 < 4.4.182; 4.9 < 4.9.182; 4.14 < 4.14.127; 4.19 < 4.19.52; 5.1 < 5.1.11 · Fixed: No fixed version is explicitly recorded in the structured CVE data.
- After
- 4.4 < 4.4.182; 4.9 < 4.9.182; 4.14 < 4.14.127; 4.19 < 4.19.52; 5.1 < 5.1.11 · 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.
- Remediation statusRemediation status changed from Awaiting fix to Patch available.github.com ↗
- Before
- Awaiting fix
- After
- Patch available
- SeveritySeverity changed from Medium to High.NIST NVD ↗
- Before
- Medium
- After
- High
- CVSS scoreCVSS score changed from 5.3 (CVSS 3.0 · CNA · CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L) to 7.5 (CVSS 3.1 · NIST NVD · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).NIST NVD ↗
- Before
- 5.3 (CVSS 3.0 · CNA · CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L)
- After
- 7.5 (CVSS 3.1 · NIST NVD · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
- Catalogue recordCVE added to the BlackTree catalogue.CNA ↗
- Affected versionsThe structured affected or fixed version information changed.Siemens ProductCERT ↗
- Before
- 4.4 < 4.4.182; 4.9 < 4.9.182; 4.14 < 4.14.127; 4.19 < 4.19.52; 5.1 < 5.1.11 · 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
- 4.4 < 4.4.182; 4.9 < 4.9.182; 4.14 < 4.14.127; 4.19 < 4.19.52; 5.1 < 5.1.11 · Fixed: Update to V1.1.5 or later version
CVE published
Fixed release or patch reference recorded
Fixed release recorded from official guidance
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.