5.5 CVE-2025-21971

Enriched by CISA Patch
 

In the Linux kernel, the following vulnerability has been resolved: net_sched: Prevent creation of classes with TC_H_ROOT The function qdisc_tree_reduce_backlog() uses TC_H_ROOT as a termination condition when traversing up the qdisc tree to update parent backlog counters. However, if a class is created with classid TC_H_ROOT, the traversal terminates prematurely at this class instead of reaching the actual root qdisc, causing parent statistics to be incorrectly maintained. In case of DRR, this could lead to a crash as reported by Mingi Cho. Prevent the creation of any Qdisc class with classid TC_H_ROOT (0xFFFFFFFF) across all qdisc types, as suggested by Jamal.
https://nvd.nist.gov/vuln/detail/CVE-2025-21971

Categories

CWE-835 : Loop with Unreachable Exit Condition ('Infinite Loop')
The product contains an iteration or loop with an exit condition that cannot be reached, i.e., an infinite loop. Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.) Chain: an operating system does not properly process malformed Open Shortest Path First (OSPF) Type/Length/Value Identifiers (TLV) (CWE-703), which can cause the process to enter an infinite loop (CWE-835) A Python machine communication platform did not account for receiving a malformed packet with a null size, causing the receiving function to never update the message buffer and be caught in an infinite loop. Chain: off-by-one error (CWE-193) leads to infinite loop (CWE-835) using invalid hex-encoded characters. Chain: self-referential values in recursive definitions lead to infinite loop. NULL UDP packet is never cleared from a queue, leading to infinite loop. Chain: web browser crashes due to infinite loop - "badlooping logic [that relies on] floating point math [CWE-1339] to exitthe loop [CWE-835]" Floating point conversion routine cycles back and forth between two different values. Floating point conversion routine cycles back and forth between two different values. Chain: improperly clearing a pointer in a linked list leads to infinite loop. Chain: an integer overflow (CWE-190) in the image size calculation causes an infinite loop (CWE-835) which sequentially allocates buffers without limits (CWE-1325) until the stack is full. Chain: A denial of service may be caused by an uninitialized variable (CWE-457) allowing an infinite loop (CWE-835) resulting from a connection to an unresponsive server.

References


 

AFFECTED (from MITRE)

Vendor Product Versions
Linux Linux
  • 066a3b5b2346febf9a655b444567b7138e3bb939 < e05d9938b1b0ac40b6054cc5fa0ccbd9afd5ed4c [affected]
  • 066a3b5b2346febf9a655b444567b7138e3bb939 < 7a82fe67a9f4d7123d8e5ba8f0f0806c28695006 [affected]
  • 066a3b5b2346febf9a655b444567b7138e3bb939 < 003d92c91cdb5a64b25a9a74cb8543aac9a8bb48 [affected]
  • 066a3b5b2346febf9a655b444567b7138e3bb939 < e5ee00607bbfc97ef1526ea95b6b2458ac9e7cb7 [affected]
  • 066a3b5b2346febf9a655b444567b7138e3bb939 < 78533c4a29ac3aeddce4b481770beaaa4f3bfb67 [affected]
  • 066a3b5b2346febf9a655b444567b7138e3bb939 < 5c3ca9cb48b51bd72bf76b8b05e24f3cd53db5e7 [affected]
  • 066a3b5b2346febf9a655b444567b7138e3bb939 < 94edfdfb9505ab608e86599d1d1e38c83816fc1c [affected]
  • 066a3b5b2346febf9a655b444567b7138e3bb939 < 0c3057a5a04d07120b3d0ec9c79568fceb9c921e [affected]
Linux Linux
  • 2.6.25 [affected]
  • < 2.6.25 [unaffected]
  • 5.4.292 ≤ 5.4.* [unaffected]
  • 5.10.236 ≤ 5.10.* [unaffected]
  • 5.15.180 ≤ 5.15.* [unaffected]
  • 6.1.132 ≤ 6.1.* [unaffected]
  • 6.6.84 ≤ 6.6.* [unaffected]
  • 6.12.20 ≤ 6.12.* [unaffected]
  • 6.13.8 ≤ 6.13.* [unaffected]
  • 6.14 ≤ * [unaffected]
© 2022 The MITRE Corporation. This work is reproduced and distributed with the permission of The MITRE Corporation.

CPE

cpe start end
Configuration 1
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* >= 2.6.26 < 5.4.292
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* >= 5.5 < 5.10.236
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* >= 5.11 < 5.15.180
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* >= 5.16 < 6.1.132
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* >= 6.2 < 6.6.84
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* >= 6.7 < 6.12.20
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* >= 6.13 < 6.13.8
cpe:2.3:o:linux:linux_kernel:2.6.25:-:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:6.14:rc6:*:*:*:*:*:*

REMEDIATION

Patch

Url
https://git.kernel.org/stable/c/003d92c91cdb5a64b25a9a74cb8543aac9a8bb48
https://git.kernel.org/stable/c/0c3057a5a04d07120b3d0ec9c79568fceb9c921e
https://git.kernel.org/stable/c/5c3ca9cb48b51bd72bf76b8b05e24f3cd53db5e7
https://git.kernel.org/stable/c/78533c4a29ac3aeddce4b481770beaaa4f3bfb67
https://git.kernel.org/stable/c/7a82fe67a9f4d7123d8e5ba8f0f0806c28695006
https://git.kernel.org/stable/c/94edfdfb9505ab608e86599d1d1e38c83816fc1c
https://git.kernel.org/stable/c/e05d9938b1b0ac40b6054cc5fa0ccbd9afd5ed4c
https://git.kernel.org/stable/c/e5ee00607bbfc97ef1526ea95b6b2458ac9e7cb7

EXPLOITS

Exploit-db.com

id description date
No known exploits

POC Github

Url
No known exploits

Other Nist (github, ...)

Url
No known exploits

CAPEC

Common Attack Pattern Enumerations and Classifications

id description severity
No entry