CVE-2021-47316

mediumpriority · track · 22EPSS 0.006 · 50 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.62% (50th) EPSS

CVSS 5.5 · medium

Is it mine?

16 products

Check your exposure

Who says so?

6 sources

cnnvd · enisa_euvd · fstec_bdu · cisa_csaf_ot

EPSS · scored 2026-10-27

In the Linux kernel, the following vulnerability has been resolved: nfsd: fix NULL dereference in nfs3svc_encode_getaclres In error cases the dentry may be NULL. Before 20798dfe249a, the encoder also checked dentry and d_really_is_positive(dentry), but that looks like overkill to me--zero status should be enough to guarantee a positive dentry. This isn't the first time we've seen an error-case NULL dereference hidden in the initialization of a local variable in an xdr encoder. But I went back through the other recent rewrites and didn't spot any similar bugs.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

FixedSIMATIC S7-1500 TM MFP - GNU/Linux subsystemsiemens_psirt
Update to V1.1.1 or later version
https://support.industry.siemens.com/cs/ww/en/view/109827684/
MitigationSIMATIC S7-1500 TM MFP - GNU/Linux subsystemsiemens_psirt
Limit access to the interactive shell of the additional GNU/Linux subssytem to trusted personnel only.
MitigationSIMATIC S7-1500 TM MFP - GNU/Linux subsystemcisa_csaf_ot
Limit access to the interactive shell of the additional GNU/Linux subssytem to trusted personnel only.
No fix availableSIMATIC S7-1500 TM MFP - GNU/Linux subsystemcisa_csaf_ot
Currently no fix is available

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5.1–7.5

v3.15.5mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 1.8 · impact 3.6

v3.15.5mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hsecondary · CISA US

v3.15.5mediumAV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondaryexploitability 3.9 · impact 3.6

v3.15.5mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hsecondary · Siemens ProductCERT DE

v3.15.1mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-476USprimaryCWE-20USCWE-20USCWE-476US

affected products (16)

Products and version ranges known to be affected.

SIMATIC S7-1500 TM MFP - GNU/Linux subsystemall versionscisa_csaf_otUS
Siemens RUGGEDCOM RST2428P (6GK6242-6PA00)≤ vers:all/*not affectedcisa_csaf_otUS
Siemens SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 family≤ vers:all/*not affectedcisa_csaf_otUS
Siemens SCALANCE XCM-/XRM-/XCH-/XRH-300 family≤ vers:all/*not affectedcisa_csaf_otUS
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem≤ vers:all/*cisa_csaf_otUS
Linux Linuxall versionsenisa_euvdEU
Linux Linux≤ 5.13enisa_euvdEU
Linux Linux< 5.13.4enisa_euvdEU
Linux Linux< 5.14enisa_euvdEU
Linux Linux20798dfe249a… → 650e6f383a6e…enisa_euvdEU
Linux Linux20798dfe249a… → ab1016d39cc0…enisa_euvdEU
Linux Linuxd505e6619107… → e79057d15d96…enisa_euvdEU
Сообщество свободного программного обеспечения Linux5.13 → 5.13.3fstec_bduRU
linux linux kernel5.13 → 5.13.4nvdUScpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem < V1.1.1≤ vers:intdot/<1.1.1siemens_psirtDE
Siemens SIMATIC S7-1500 TM MFP - GNU/Linux subsystem≤ vers:intdot/<1.1.1siemens_psirtDE

advisories (4)

Vendor and ecosystem advisories describing this.

SSA-265688SSA-265688: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 TM MFP V1.12024-04-09csaf · siemens_psirtDE
Multiple vulnerabilities have been identified in the additional GNU/Linux subsystem of the SIMATIC S7-1500 TM MFP V1.1. Siemens has released a new version for SIMATIC S7-1500 TM MFP - GNU/Linux subsystem and recommends to update to the latest version. Siemens is preparing further fixes and recommends specific mitigations for products where fixes are not or not yet available. SIMATIC S7-1500 TM MFP V1.1 is no longer maintained and there won't be any update to the CVE list anymore. Please update to the latest version. Note: This SSA advises vulnerabilities for firmware version V1.1 only; for version V1.1.1 refer to SSA-784472.
SSA-355557SSA-355557: Multiple Vulnerabilities in Third-Party Components in SINEC OS before V3.22025-08-12csaf · siemens_psirtDE
SINEC OS before V3.2 contains third-party components with multiple vulnerabilities. Siemens has released new versions for the affected products and recommends to update to the latest versions.
ICSA-24-102-01Siemens SIMATIC S7-1500 TM MFP2024-04-09icsa · cisa_csaf_otUS
Multiple vulnerabilities have been identified in the additional GNU/Linux subsystem of the SIMATIC S7-1500 TM MFP V1.1. Siemens is preparing fix versions and recommends specific countermeasures for products where fixes are not, or not yet available.
ICSA-25-226-07Siemens Third-Party Components in SINEC OS2025-08-12icsa · cisa_csaf_otUS
SINEC OS before V3.2 contains third-party components with multiple vulnerabilities. Siemens has released new versions for the affected products and recommends to update to the latest versions.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cisa_csaf_ot nvd siemens_psirt NVD CVE.org MITRE

published 2024-05-21modified 2026-10-14

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references (11)

External citations — patches, advisories, analysis.

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