net/sched: sch_fq: fix integer overflow of "credit"
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 2 fixed, 3 without a fix
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-190 and the CVSS impact.
Summary
In the Linux kernel, the following vulnerability has been resolved: net/sched: sch_fq: fix integer overflow of "credit" if sch_fq is configured with "initial quantum" having values greater than INT_MAX, the first assignment of "credit" does signed integer overflow to a very negative value. In this situation, the syzkaller script provided by Cristoph triggers the CPU soft-lockup warning even with few sockets. It's not an infinite loop, but "credit" wasn't probably meant to be minus 2Gb for each new flow. Capping "initial quantum" to INT_MAX proved to fix the issue. v2: validation of "initial quantum" is done in fq_policy, instead of open coding in fq_change() _ suggested by Jakub Kicinski
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 3.12 and later | 5.10.180, 5.15.111, 6.1.28, 6.2.15, 6.3.2, 6.4 | Patch available | CNA |
- Linux VendorLinux Affected 3.12 and later Fixed in 5.10.180, 5.15.111, 6.1.28, 6.2.15, 6.3.2, 6.4 Patch available CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 3.12 to before 5.10.180; 5.11 to before 5.15.111; 5.16 to before 6.1.28; 6.2 to before 6.2.15; 6.3 to before 6.3.2 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 3.12 to before 5.10.180; 5.11 to before 5.15.111; 5.16 to before 6.1.28; 6.2 to before 6.2.15; 6.3 to before 6.3.2 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.10.180, 5.15.111, 6.1.28, 6.2.15, 6.3.2, 6.4
Red Hat 2 advisories
- RHSA-2023:7077 Released 2023-11-14 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat CodeReady Linux Builder (v. 8) kernel-tools-libs-devel-4.18.0-513.5.1.el8_9
- Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-513.5.1.el8_9, kernel-4.18.0-513.5.1.el8_9, kernel-abi-stablelists-4.18.0-513.5.1.el8_9 +19
- RHSA-2023:6583 Released 2023-11-07 · Red Hat rating Importantkernel security, bug fix, and enhancement update
- Red Hat CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-362.8.1.el9_3, libperf-5.14.0-362.8.1.el9_3
- Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-362.8.1.el9_3, kernel-64k-debug-devel-matched-5.14.0-362.8.1.el9_3, kernel-64k-devel-5.14.0-362.8.1.el9_3 +11
- Red Hat Enterprise Linux BaseOS (v. 9) bpftool-7.2.0-362.8.1.el9_3, kernel-5.14.0-362.8.1.el9_3, kernel-64k-5.14.0-362.8.1.el9_3 +29
- Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-362.8.1.el9_3, kernel-rt-core-5.14.0-362.8.1.el9_3, kernel-rt-debug-5.14.0-362.8.1.el9_3 +9
- Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-362.8.1.el9_3, kernel-rt-core-5.14.0-362.8.1.el9_3, kernel-rt-debug-5.14.0-362.8.1.el9_3 +11
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 7 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
| Red Hat CodeReady Linux Builder (v. 8) | Fixed | RHSA-2023:7077 |
| Red Hat Enterprise Linux BaseOS (v. 8) | Fixed | RHSA-2023:7077 |
Not affected: 2 products
- Red Hat Enterprise Linux 10
- Red Hat Enterprise Linux 6
Timeline
- 2026-10-02 Threatist record created from CVE-2023-53624
- 2026-10-03 Alias added: GHSA-xhfr-4q2x-5mx4
- 2026-11-05 CISA SSVC decision points changed
References
Patch 6
- https://git.kernel.org/stable/c/4b8a05e3801661a0438fcd0cdef181030d966a5a
- https://git.kernel.org/stable/c/d0b43125ec892aeb1b03e5df5aab595097da225a
- https://git.kernel.org/stable/c/4fbefeab88c6e79753a25099d455d3d59d2946b4
- https://git.kernel.org/stable/c/85f24cb2f10b2b0f2882e5786a09b4790bb3a0ad
- https://git.kernel.org/stable/c/2322462d6f9ad4874f4e3c63df3b5cc00cb1acbd
- https://git.kernel.org/stable/c/7041101ff6c3073fd8f2e99920f535b111c929cb
More Linux Kernel vulnerabilities
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- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2023-53624 · CVE Program
- CVE-2023-53624 · NVD
- FIRST EPSS
- GHSA-xhfr-4q2x-5mx4 · GitHub Advisory Database · CC BY 4.0
- CVE-2023-53624 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences