CVE-2025-21647

highpriority · track · 28EPSS 0.003 · 20 %ileDEEURUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.28% (20th) EPSS
CVSS 7.1 · high
Is it mine?
68 products
Check your exposure
Who says so?
7 sources
cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-23

In the Linux kernel, the following vulnerability has been resolved: sched: sch_cake: add bounds checks to host bulk flow fairness counts Even though we fixed a logic error in the commit cited below, syzbot still managed to trigger an underflow of the per-host bulk flow counters, leading to an out of bounds memory access. To avoid any such logic errors causing out of bounds memory accesses, this commit factors out all accesses to the per-host bulk flow counters to a series of helpers that perform bounds-checking before any increments and decrements. This also has the benefit of improving readability by moving the conditional checks for the flow mode into these helpers, instead of having them spread out throughout the code (which was the cause of the original logic error). As part of this change, the flow quantum calculation is consolidated into a helper function, which means that the dithering applied to the ost load scaling is now applied both in the DRR rotation and when a sparse flow's quantum is first initiated. The only user-visible effect of this is that the maximum packet size that can be sent while a flow stays sparse will now vary with +/- one byte in some cases. This should not make a noticeable difference in practice, and thus it's not worth complicating the code to preserve the old behaviour.

01

remediations

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

A vendor fix is available.

  • Fixedkernel-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-abi-stablelists-0:5.14.0-570.86.1.el9_6.noarch as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-core-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-cross-headers-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-debug-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-debug-core-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-debug-devel-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-debug-devel-matched-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-debug-modules-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-debug-modules-core-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-debug-modules-extra-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-debug-uki-virt-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-devel-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-devel-matched-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-doc-0:5.14.0-570.86.1.el9_6.noarch as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-headers-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-modules-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-modules-core-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-modules-extra-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-tools-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-tools-libs-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-tools-libs-devel-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-uki-virt-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedkernel-uki-virt-addons-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedlibperf-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedperf-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedpython3-perf-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedrtla-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • Fixedrv-0:5.14.0-570.86.1.el9_6.x86_64 as component of SUSE Liberty Linux 9.6 EMSsuse_csaf

    To install this SUSE Security Update use the SUSE recommended installation methods like YaST online_update or "zypper patch".

  • 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.

  • WorkaroundSIMATIC S7-1500 TM MFP - BIOSsiemens_psirt

    Only build and run applications from trusted sources

  • WorkaroundSIMATIC S7-1500 TM MFP - BIOScisa_csaf_ot

    Only build and run applications from trusted sources

  • No fix availableSIMATIC S7-1500 TM MFP - GNU/Linux subsystemsiemens_psirt

    Currently no fix is available

  • No fix availableSIMATIC S7-1500 TM MFP - BIOSsiemens_psirt

    Currently no fix is available

  • No fix availableSIMATIC S7-1500 TM MFP - GNU/Linux subsystemcisa_csaf_ot

    Currently no fix is available

  • No fix availableSIMATIC S7-1500 TM MFP - BIOScisa_csaf_ot

    Currently no fix is available

02

cvss

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

7.8
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.5–7.8

v3.17.1highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Hprimary · NVD / NIST USexploitability 1.8 · impact 5.2
v3.17.1highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Hsecondary · CISA US
v3.17.8highAV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU
v3.17.3highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:Hsecondary · ENISA EU
v3.17.3highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:Hsecondaryexploitability 1.8 · impact 5.5
v3.17.1highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:Hsecondary · Siemens ProductCERT DE
v3.16.5mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
v3.17.8highCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · SUSE Product Security
03

weaknesses

The CWE weakness classes this flaw belongs to.

04

affected products (68)

Products and version ranges known to be affected.

showing 20 of 68
05

advisories (8)

Vendor and ecosystem advisories describing this.

  • RHSA-2026:2352security update for kernel2026-02-09csaf · suse_csafDE

    security update for kernel

  • 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-503939SSA-503939: Vulnerabilities in the BIOS of the SIMATIC S7-1500 TM MFP2025-03-11csaf · siemens_psirtDE

    Multiple vulnerabilities have been identified in the BIOS of the SIMATIC S7-1500 TM MFP. Siemens is preparing fix versions and recommends specific countermeasures for products where fixes are not, or not yet available.

  • WID-SEC-W-2025-0119Linux Kernel: Mehrere SchwachstellenDeutsch2025-01-19csaf · cert_bundDE

    Ein lokaler Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen Denial of Service Angriff durchzuführen oder andere nicht spezifizierte Auswirkungen zu verursachen.

  • WID-SEC-W-2025-1439Dell Secure Connect Gateway: Mehrere Schwachstellen ermöglichen nicht spezifizierten AngriffDeutsch2025-06-30csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in Dell Secure Connect Gateway ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen.

  • WID-SEC-W-2026-2253IBM Security Verify Access: Mehrere SchwachstellenDeutsch2026-07-08csaf · cert_bundDE

    Ein Angreifer kann mehrere Schwachstellen in IBM Security Verify Access ausnutzen, um erweiterte Berechtigungen zu erlangen, beliebigen Code auszuführen, Sicherheitsmaßnahmen zu umgehen, Daten zu manipulieren, sensible Informationen offenzulegen und andere, nicht näher bezeichnete Angriffe durchzuführen.

  • 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-25-072-03Siemens SIMATIC S7-1500 TM MFP2025-03-11icsa · cisa_csaf_otUS

    Multiple vulnerabilities have been identified in the BIOS of the SIMATIC S7-1500 TM MFP. Siemens is preparing fix versions and recommends specific countermeasures for products where fixes are not, or not yet available.

06

also known as (4)

Other names and identifiers for this entity.

07

sources

Which sources assert this record, and when.

09

references (24)

External citations — patches, advisories, analysis.

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