Linux Kernel: Race Condition (CVE-2024-49998)
Published Last modified Sources: Siemens ProductCERT, Debian, Debian LTS, SUSE, BSI, CVE.org, Msrc Update Guide, EUVD
What is affected, what to do
In the Linux kernel, the following vulnerability has been resolved: net: dsa: improve shutdown sequence Alexander Sverdlin presents 2 problems during shutdown with the lan9303 driver. One is specific to lan9303 and the other just happens to reproduce there.
The available sources name no fixed version. Check the vendor guidance in the references below.
Conflicting version data — version display is hidden until the data is resolved.
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Metrics
4.7
Priority
XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.
Source: NVD, CVSS v3
4.7
CVSS v3
Severity Medium on the scale from 0 to 10.
Source: Siemens ProductCERT, Debian, Debian LTS, SUSE, BSI, CVE.org, Msrc Update Guide, EUVD
0.2 %
EPSS score
Low — model estimates < 1% exploitation likelihood.
Source: FIRST EPSS, percentile 8.3
Show all metrics
- Severity
- Medium
Priority (0–325)
The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?
Read in glossary- 30.66 Methodology
Exploit maturity
An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.
Read in glossary- no public PoC known
XIEM Effective CVSS
XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.
Read in glossary- 4.7 Methodology
CVSS v3
CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.
Read in glossary- 4.7
EPSS score
The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.
Read in glossary- 0.2 %
- Low — model estimates < 1% exploitation likelihood.
EPSS percentile
The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.
Read in glossary- 8.3
- Low — this CVE sits in the lower 10% of all CVEs scored today.
KEV status
The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.
Read in glossary- —
- Published
- CISA assessment (SSVC)
- Exploitation: none known · not automatable · Technical impact: partial
- Source: CISA Vulnrichment, as of 22 October 2024
Detection rules
No NEOSEC detection rule is available for this vulnerability yet.
Classification under NIS2 and CRA
Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.
NIS2
NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.
Read in glossary- Handle the vulnerability in regular vulnerability handling under Art. 21(2)(e) NIS2.
CRA
The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.
Read in glossary- From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
ISO/IEC 27001
ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.
Read in glossary- Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.
Description
In the Linux kernel, the following vulnerability has been resolved: net: dsa: improve shutdown sequence Alexander Sverdlin presents 2 problems during shutdown with the lan9303 driver. One is specific to lan9303 and the other just happens to reproduce there. The first problem is that lan9303 is unique among DSA drivers in that it calls dev_get_drvdata() at "arbitrary runtime" (not probe, not shutdown, not remove): phy_state_machine() -> ... -> dsa_user_phy_read() -> ds->ops->phy_read() -> lan9303_phy_read() -> chip->ops->phy_read() -> lan9303_mdio_phy_read() -> dev_get_drvdata() But we never stop the phy_state_machine(), so it may continue to run after dsa_switch_shutdown(). Our common pattern in all DSA drivers is to set drvdata to NULL to suppress the remove() method that may come afterwards. But in this case it will result in an NPD. The second problem is that the way in which we set dp->conduit->dsa_ptr = NULL; is concurrent with receive packet processing. dsa_switch_rcv() checks once whether dev->dsa_ptr is NULL, but afterwards, rather than continuing to use that non-NULL value, dev->dsa_ptr is dereferenced again and again without NULL checks: dsa_conduit_find_user() and many other places. In between dereferences, there is no locking to ensure that what was valid once continues to be valid. Both problems have the common aspect that closing the conduit interface solves them. In the first case, dev_close(conduit) triggers the NETDEV_GOING_DOWN event in dsa_user_netdevice_event() which closes user ports as well. dsa_port_disable_rt() calls phylink_stop(), which synchronously stops the phylink state machine, and ds->ops->phy_read() will thus no longer call into the driver after this point. In the second case, dev_close(conduit) should do this, as per Documentation/networking/driver.rst: | Quiescence | ---------- | | After the ndo_stop routine has been called, the hardware must | not receive or transmit any data. All in flight packets must | be aborted. If necessary, poll or wait for completion of | any reset commands. So it should be sufficient to ensure that later, when we zeroize conduit->dsa_ptr, there will be no concurrent dsa_switch_rcv() call on this conduit. The addition of the netif_device_detach() function is to ensure that ioctls, rtnetlinks and ethtool requests on the user ports no longer propagate down to the driver - we're no longer prepared to handle them. The race condition actually did not exist when commit 0650bf52b31f ("net: dsa: be compatible with masters which unregister on shutdown") first introduced dsa_switch_shutdown(). It was created later, when we stopped unregistering the user interfaces from a bad spot, and we just replaced that sequence with a racy zeroization of conduit->dsa_ptr (one which doesn't ensure that the interfaces aren't up).
Source: siemens_advisory, Debian Security Advisories, Debian LTS Advisories, suse_csaf, BSI WID Portal, BSI CSAF, NVD (NIST), CVE.org (MITRE), cvelistv5, Microsoft Security Update Guide, ENISA EUVD
Affected products
The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.
| Affected versions | Fixed in | ||
|---|---|---|---|
| Linux | Linux |
|
|
| Siemens | SIMATIC S7 |
|
|
Vendors and products
Affected operating systems
| Linux | debian | linux | bookworm |
| Linux | debian | linux-6.1 | bullseye |
| Linux | linux | linux_kernel | 6.12 |
| Linux | linux | linux_kernel | — |
References & sources
- git.kernel.orgstable/c/87bd909a7014e32790e8c759d5b7694a95778ca5
- git.kernel.orgstable/c/ab9e90619b6339becc5415647ae154a9a46a044d
- git.kernel.orgstable/c/2e93bf719462ac6d23c881c8b93e5dc9bf5ab7f5
- git.kernel.orgstable/c/ab5d3420a1120950703dbdc33698b28a6ebc3d23
- git.kernel.orgstable/c/b4a65d479213fe84ecb14e328271251eebe69492
- git.kernel.orgstable/c/6c24a03a61a245fe34d47582898331fa034b6ccd
- Siemens ProductCERTproductcert/html/ssa-082556.html
- Siemens ProductCERTproductcert/html/ssa-019113.html
- Siemens ProductCERTproductcert/html/ssa-457936.html
- Siemens ProductCERTproductcert/html/ssa-784472.html
Changes to this CVE
Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).
Record modifiedLinux
New references:- https://git.kernel.org/stable/c/2e93bf719462ac6d23c881c8b93e5dc9bf5ab7f5
- https://git.kernel.org/stable/c/6c24a03a61a245fe34d47582898331fa034b6ccd
- https://git.kernel.org/stable/c/87bd909a7014e32790e8c759d5b7694a95778ca5
- https://git.kernel.org/stable/c/ab5d3420a1120950703dbdc33698b28a6ebc3d23
and 2 more references
Show 15 original changes
Individual changes of this event as published by NVD Type Action Before After Reference added —https://git.kernel.org/stable/c/2e93bf719462ac6d23c881c8b93e5dc9bf5ab7f5Reference added —https://git.kernel.org/stable/c/6c24a03a61a245fe34d47582898331fa034b6ccdReference added —https://git.kernel.org/stable/c/87bd909a7014e32790e8c759d5b7694a95778ca5Reference added —https://git.kernel.org/stable/c/ab5d3420a1120950703dbdc33698b28a6ebc3d23Reference added —https://git.kernel.org/stable/c/ab9e90619b6339becc5415647ae154a9a46a044dReference added —https://git.kernel.org/stable/c/b4a65d479213fe84ecb14e328271251eebe69492Reference removed https://git.kernel.org/stable/c/2e93bf719462ac6d23c881c8b93e5dc9bf5ab7f5—Reference removed https://git.kernel.org/stable/c/6c24a03a61a245fe34d47582898331fa034b6ccd—Reference removed https://git.kernel.org/stable/c/87bd909a7014e32790e8c759d5b7694a95778ca5—Reference removed https://git.kernel.org/stable/c/ab5d3420a1120950703dbdc33698b28a6ebc3d23—Reference removed https://git.kernel.org/stable/c/ab9e90619b6339becc5415647ae154a9a46a044d—Reference removed https://git.kernel.org/stable/c/b4a65d479213fe84ecb14e328271251eebe69492—Reference type removed https://git.kernel.org/stable/c/6c24a03a61a245fe34d47582898331fa034b6ccd Types: Patch—Reference type removed https://git.kernel.org/stable/c/ab5d3420a1120950703dbdc33698b28a6ebc3d23 Types: Patch—Reference type removed https://git.kernel.org/stable/c/b4a65d479213fe84ecb14e328271251eebe69492 Types: Patch—Source identifier: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Record modifiedSiemens ADP
Show 7 original changes
Individual changes of this event as published by NVD Type Action Before After Affected versions (publisher) added —Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2024/49xxx/CVE-2024-49998.json">CVE-2024-49998</a>Reference added —https://cert-portal.siemens.com/productcert/html/ssa-019113.htmlReference added —https://cert-portal.siemens.com/productcert/html/ssa-082556.htmlReference added —https://cert-portal.siemens.com/productcert/html/ssa-457936.htmlReference added —https://cert-portal.siemens.com/productcert/html/ssa-784472.htmlReference removed https://cert-portal.siemens.com/productcert/html/ssa-019113.html—Reference removed https://cert-portal.siemens.com/productcert/html/ssa-082556.html—Source identifier: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
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<a href="https://intel.neosec.eu/en/cve/CVE-2024-49998"><img src="https://intel.neosec.eu/badge/cve/CVE-2024-49998.svg?lang=en" alt="CVE-2024-49998 – NEOSEC Intel" height="20"></a>