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TI-2023-03529 Aliases CVE-2023-3776GHSA-fcg7-9x44-gx43

Use-after-free in Linux kernel's net/sched: cls_fw component

Priority LOW 37CWE-416Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.

Summary

A use-after-free vulnerability in the Linux kernel's net/sched: cls_fw component can be exploited to achieve local privilege escalation. If tcf_change_indev() fails, fw_set_parms() will immediately return an error after incrementing or decrementing the reference counter in tcf_bind_filter(). If an attacker can control the reference counter and set it to zero, they can cause the reference to be freed, leading to a use-after-free vulnerability. We recommend upgrading past commit 0323bce598eea038714f941ce2b22541c46d488f.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00508 43rd percentileScored 2026-11-07
Fix Fixed Kernel (Linux): 6.5Red Hat: 25 advisories

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxKernel2.6 to before 6.56.5Patch availableCNA
  • Kernel VendorLinux Affected 2.6 to before 6.5 Fixed in 6.5 Patch available CNA

CPE configurations NVD · 5

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*2.6.12 to before 4.14.322; 4.15 to before 4.19.291; 4.20 to before 5.4.251; 5.5 to before 5.10.188; 5.11 to before 5.15.121; 5.16 to before 6.1.40; 6.2 to before 6.4.5VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.5:rc1:*:*:*:*:*:*6.5 rc1VulnerableLinux
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*10.0VulnerableDebian
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*11.0VulnerableDebian
cpe:2.3:o:debian:debian_linux:12.0:*:*:*:*:*:*:*12.0VulnerableDebian
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 2.6.12 to before 4.14.322; 4.15 to before 4.19.291; 4.20 to before 5.4.251; 5.5 to before 5.10.188; 5.11 to before 5.15.121; 5.16 to before 6.1.40; 6.2 to before 6.4.5 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.5:rc1:*:*:*:*:*:* Versions 6.5 rc1 Vulnerable ·Linux
  • cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:* Versions 10.0 Vulnerable ·Debian
  • cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:* Versions 11.0 Vulnerable ·Debian
  • cpe:2.3:o:debian:debian_linux:12.0:*:*:*:*:*:*:* Versions 12.0 Vulnerable ·Debian

Remediation

  • Fix · CNA Kernel (Linux) Fixed in 6.5

Red Hat 25 advisories

  • RHSA-2024:1831 Released 2024-04-16 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux Server (v. 6 ELS) kernel-2.6.32-754.53.1.el6, kernel-abi-whitelists-2.6.32-754.53.1.el6, kernel-debug-2.6.32-754.53.1.el6 +7
    • Red Hat Enterprise Linux Server Optional (v. 6 ELS) python-perf-2.6.32-754.53.1.el6
  • RHSA-2024:0262 Released 2024-01-16 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux Server AUS (v. 7.7) bpftool-3.10.0-1062.82.1.el7, kernel-3.10.0-1062.82.1.el7, kernel-abi-whitelists-3.10.0-1062.82.1.el7 +8
    • Red Hat Enterprise Linux Server Optional AUS (v. 7.7) kernel-tools-libs-devel-3.10.0-1062.82.1.el7
  • RHSA-2023:7423 Released 2023-11-21 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux Client (v. 7) bpftool-3.10.0-1160.105.1.el7, kernel-3.10.0-1160.105.1.el7, kernel-abi-whitelists-3.10.0-1160.105.1.el7 +8
    • Red Hat Enterprise Linux Client Optional (v. 7) kernel-tools-libs-devel-3.10.0-1160.105.1.el7
    • Red Hat Enterprise Linux ComputeNode Optional (v. 7) kernel-tools-libs-devel-3.10.0-1160.105.1.el7
    • Red Hat Enterprise Linux Server (v. 7) bpftool-3.10.0-1160.105.1.el7, kernel-3.10.0-1160.105.1.el7, kernel-abi-whitelists-3.10.0-1160.105.1.el7 +11
    • Red Hat Enterprise Linux Server Optional (v. 7) kernel-debug-devel-3.10.0-1160.105.1.el7, kernel-tools-libs-devel-3.10.0-1160.105.1.el7
    • Red Hat Enterprise Linux Workstation (v. 7) bpftool-3.10.0-1160.105.1.el7, kernel-3.10.0-1160.105.1.el7, kernel-abi-whitelists-3.10.0-1160.105.1.el7 +8
    • Red Hat Enterprise Linux Workstation Optional (v. 7) kernel-tools-libs-devel-3.10.0-1160.105.1.el7
Show 22 more Red Hat advisories
  • RHSA-2023:7434 Released 2023-11-21 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat Enterprise Linux BaseOS AUS (v. 8.2) bpftool-4.18.0-193.119.1.el8_2, kernel-4.18.0-193.119.1.el8_2, kernel-abi-whitelists-4.18.0-193.119.1.el8_2 +14
    • Red Hat Enterprise Linux BaseOS E4S (v. 8.2) bpftool-4.18.0-193.119.1.el8_2, kernel-4.18.0-193.119.1.el8_2, kernel-abi-whitelists-4.18.0-193.119.1.el8_2 +14
    • Red Hat Enterprise Linux BaseOS TUS (v. 8.2) bpftool-4.18.0-193.119.1.el8_2, kernel-4.18.0-193.119.1.el8_2, kernel-abi-whitelists-4.18.0-193.119.1.el8_2 +14
  • RHSA-2023:7419 Released 2023-11-21 · Red Hat rating Important
    kpatch-patch security update
    • Red Hat Enterprise Linux Server (v. 7) kpatch-patch-3_10_0-1160_102_1-1-1.el7, kpatch-patch-3_10_0-1160_90_1-1-4.el7, kpatch-patch-3_10_0-1160_92_1-1-4.el7 +2
  • RHSA-2023:7431 Released 2023-11-21 · Red Hat rating Important
    kernel-rt security update
    • Red Hat Enterprise Linux Real Time TUS (v. 8.2) kernel-rt-4.18.0-193.119.1.rt13.170.el8_2, kernel-rt-core-4.18.0-193.119.1.rt13.170.el8_2, kernel-rt-debug-4.18.0-193.119.1.rt13.170.el8_2 +7
    • Red Hat Enterprise Linux Real Time for NFV TUS (v. 8.2) kernel-rt-4.18.0-193.119.1.rt13.170.el8_2, kernel-rt-core-4.18.0-193.119.1.rt13.170.el8_2, kernel-rt-debug-4.18.0-193.119.1.rt13.170.el8_2 +9
  • RHSA-2023:7424 Released 2023-11-21 · Red Hat rating Important
    kernel-rt security update
    • Red Hat Enterprise Linux for Real Time (v. 7) kernel-rt-3.10.0-1160.105.1.rt56.1256.el7, kernel-rt-debug-3.10.0-1160.105.1.rt56.1256.el7, kernel-rt-debug-devel-3.10.0-1160.105.1.rt56.1256.el7 +4
    • Red Hat Enterprise Linux for Real Time for NFV (v. 7) kernel-rt-3.10.0-1160.105.1.rt56.1256.el7, kernel-rt-debug-3.10.0-1160.105.1.rt56.1256.el7, kernel-rt-debug-devel-3.10.0-1160.105.1.rt56.1256.el7 +7
  • RHSA-2023:7417 Released 2023-11-21 · Red Hat rating Important
    kpatch-patch security update
    • Red Hat Enterprise Linux BaseOS E4S (v. 8.2) kpatch-patch-4_18_0-193_109_1-1-3.el8_2, kpatch-patch-4_18_0-193_113_1-1-2.el8_2, kpatch-patch-4_18_0-193_116_1-1-1.el8_2
  • RHSA-2023:7411 Released 2023-11-21 · Red Hat rating Important
    kpatch-patch security update
    • Red Hat Enterprise Linux BaseOS EUS (v.9.0) kpatch-patch-5_14_0-70_53_1-1-5.el9_0, kpatch-patch-5_14_0-70_58_1-1-4.el9_0, kpatch-patch-5_14_0-70_64_1-1-3.el9_0 +2
  • RHSA-2023:7398 Released 2023-11-21 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat CodeReady Linux Builder EUS (v.8.6) kernel-tools-libs-devel-4.18.0-372.80.1.el8_6
    • Red Hat Enterprise Linux BaseOS EUS (v.8.6) bpftool-4.18.0-372.80.1.el8_6, kernel-4.18.0-372.80.1.el8_6, kernel-abi-stablelists-4.18.0-372.80.1.el8_6 +19
    • Red Hat Virtualization 4 Hypervisor for RHEL 8 kernel-devel-4.18.0-372.80.1.el8_6, perf-4.18.0-372.80.1.el8_6
  • RHSA-2023:7410 Released 2023-11-21 · Red Hat rating Important
    kpatch-patch security update
    • Red Hat Enterprise Linux BaseOS EUS (v.8.6) kpatch-patch-4_18_0-372_52_1-1-5.el8_6, kpatch-patch-4_18_0-372_57_1-1-4.el8_6, kpatch-patch-4_18_0-372_64_1-1-3.el8_6 +2
  • RHSA-2023:7382 Released 2023-11-21 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat CodeReady Linux Builder EUS (v.9.0) kernel-tools-libs-devel-5.14.0-70.80.1.el9_0
    • Red Hat Enterprise Linux AppStream EUS (v.9.0) kernel-debug-devel-5.14.0-70.80.1.el9_0, kernel-debug-devel-matched-5.14.0-70.80.1.el9_0, kernel-devel-5.14.0-70.80.1.el9_0 +5
    • Red Hat Enterprise Linux BaseOS EUS (v.9.0) bpftool-5.14.0-70.80.1.el9_0, kernel-5.14.0-70.80.1.el9_0, kernel-abi-stablelists-5.14.0-70.80.1.el9_0 +14
  • RHSA-2023:7389 Released 2023-11-21 · Red Hat rating Important
    kernel-rt security update
    • Red Hat Enterprise Linux Real Time EUS (v.9.0) kernel-rt-5.14.0-70.80.1.rt21.151.el9_0, kernel-rt-core-5.14.0-70.80.1.rt21.151.el9_0, kernel-rt-debug-5.14.0-70.80.1.rt21.151.el9_0 +7
    • Red Hat Enterprise Linux Real Time for NFV EUS (v.9.0) kernel-rt-5.14.0-70.80.1.rt21.151.el9_0, kernel-rt-core-5.14.0-70.80.1.rt21.151.el9_0, kernel-rt-debug-5.14.0-70.80.1.rt21.151.el9_0 +9
  • RHSA-2023:7294 Released 2023-11-15 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux Server AUS (v. 7.6) bpftool-3.10.0-957.108.1.el7, kernel-3.10.0-957.108.1.el7, kernel-abi-whitelists-3.10.0-957.108.1.el7 +8
    • Red Hat Enterprise Linux Server Optional AUS (v. 7.6) kernel-tools-libs-devel-3.10.0-957.108.1.el7
  • RHSA-2023:6813 Released 2023-11-08 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat Enterprise Linux BaseOS E4S (v. 8.1) bpftool-4.18.0-147.94.1.el8_1, kernel-4.18.0-147.94.1.el8_1, kernel-abi-whitelists-4.18.0-147.94.1.el8_1 +14
  • RHSA-2023:6799 Released 2023-11-08 · Red Hat rating Important
    kpatch-patch security update
    • Red Hat Enterprise Linux BaseOS E4S (v. 8.1) kpatch-patch-4_18_0-147_83_1-1-5.el8_1, kpatch-patch-4_18_0-147_85_1-1-3.el8_1, kpatch-patch-4_18_0-147_87_1-1-2.el8_1 +1
  • RHSA-2023:5794 Released 2023-10-17 · Red Hat rating Important
    kernel-rt security update
    • Red Hat Enterprise Linux NFV TUS (v.8.4) kernel-rt-4.18.0-305.108.1.rt7.183.el8_4, kernel-rt-core-4.18.0-305.108.1.rt7.183.el8_4, kernel-rt-debug-4.18.0-305.108.1.rt7.183.el8_4 +9
    • Red Hat Enterprise Linux RT TUS (v.8.4) kernel-rt-4.18.0-305.108.1.rt7.183.el8_4, kernel-rt-core-4.18.0-305.108.1.rt7.183.el8_4, kernel-rt-debug-4.18.0-305.108.1.rt7.183.el8_4 +7
  • RHSA-2023:5775 Released 2023-10-17 · Red Hat rating Important
    kpatch-patch security update
    • Red Hat Enterprise Linux BaseOS E4S (v.8.4) kpatch-patch-4_18_0-305_103_1-1-1.el8_4, kpatch-patch-4_18_0-305_82_1-1-5.el8_4, kpatch-patch-4_18_0-305_86_2-1-4.el8_4 +3
  • RHSA-2023:5628 Released 2023-10-10 · Red Hat rating Important
    kernel security and bug fix update
    • Red Hat Enterprise Linux BaseOS AUS (v.8.4) bpftool-4.18.0-305.108.1.el8_4, kernel-4.18.0-305.108.1.el8_4, kernel-abi-stablelists-4.18.0-305.108.1.el8_4 +14
    • Red Hat Enterprise Linux BaseOS E4S (v.8.4) bpftool-4.18.0-305.108.1.el8_4, kernel-4.18.0-305.108.1.el8_4, kernel-abi-stablelists-4.18.0-305.108.1.el8_4 +19
    • Red Hat Enterprise Linux BaseOS TUS (v.8.4) bpftool-4.18.0-305.108.1.el8_4, kernel-4.18.0-305.108.1.el8_4, kernel-abi-stablelists-4.18.0-305.108.1.el8_4 +14
  • RHSA-2023:5244 Released 2023-09-19 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-477.27.1.el8_8, kernel-4.18.0-477.27.1.el8_8, kernel-abi-stablelists-4.18.0-477.27.1.el8_8 +19
    • Red Hat Enterprise Linux CRB (v. 8) kernel-tools-libs-devel-4.18.0-477.27.1.el8_8
  • RHSA-2023:5255 Released 2023-09-19 · Red Hat rating Important
    kernel-rt security and bug fix update
    • Red Hat Enterprise Linux NFV (v. 8) kernel-rt-4.18.0-477.27.1.rt7.290.el8_8, kernel-rt-core-4.18.0-477.27.1.rt7.290.el8_8, kernel-rt-debug-4.18.0-477.27.1.rt7.290.el8_8 +9
    • Red Hat Enterprise Linux RT (v. 8) kernel-rt-4.18.0-477.27.1.rt7.290.el8_8, kernel-rt-core-4.18.0-477.27.1.rt7.290.el8_8, kernel-rt-debug-4.18.0-477.27.1.rt7.290.el8_8 +7
  • RHSA-2023:5221 Released 2023-09-19 · Red Hat rating Important
    kpatch-patch security update
    • Red Hat Enterprise Linux BaseOS (v. 8) kpatch-patch-4_18_0-477_10_1-1-3.el8_8, kpatch-patch-4_18_0-477_13_1-1-2.el8_8, kpatch-patch-4_18_0-477_15_1-1-2.el8_8 +1
  • RHSA-2023:5069 Released 2023-09-12 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-284.30.1.el9_2, kernel-64k-debug-devel-matched-5.14.0-284.30.1.el9_2, kernel-64k-devel-5.14.0-284.30.1.el9_2 +10
    • Red Hat Enterprise Linux BaseOS (v. 9) bpftool-7.0.0-284.30.1.el9_2, kernel-5.14.0-284.30.1.el9_2, kernel-64k-5.14.0-284.30.1.el9_2 +29
    • Red Hat Enterprise Linux CRB (v. 9) kernel-tools-libs-devel-5.14.0-284.30.1.el9_2
  • RHSA-2023:5093 Released 2023-09-12 · Red Hat rating Important
    kpatch-patch security update
    • Red Hat Enterprise Linux BaseOS (v. 9) kpatch-patch-5_14_0-284_11_1-1-5.el9_2, kpatch-patch-5_14_0-284_18_1-1-4.el9_2, kpatch-patch-5_14_0-284_25_1-1-3.el9_2
  • RHSA-2023:5091 Released 2023-09-12 · Red Hat rating Important
    kernel-rt security and bug fix update
    • Red Hat Enterprise Linux NFV (v. 9) kernel-rt-5.14.0-284.30.1.rt14.315.el9_2, kernel-rt-core-5.14.0-284.30.1.rt14.315.el9_2, kernel-rt-debug-5.14.0-284.30.1.rt14.315.el9_2 +11
    • Red Hat Enterprise Linux RT (v. 9) kernel-rt-5.14.0-284.30.1.rt14.315.el9_2, kernel-rt-core-5.14.0-284.30.1.rt14.315.el9_2, kernel-rt-debug-5.14.0-284.30.1.rt14.315.el9_2 +9

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat CodeReady Linux Builder EUS (v.8.6)Fixed RHSA-2023:7398
Red Hat CodeReady Linux Builder EUS (v.9.0)Fixed RHSA-2023:7382
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2023:5069
Red Hat Enterprise Linux AppStream EUS (v.9.0)Fixed RHSA-2023:7382
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2023:5221, RHSA-2023:5244
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2023:5069, RHSA-2023:5093
Red Hat Enterprise Linux BaseOS AUS (v. 8.2)Fixed RHSA-2023:7434
Red Hat Enterprise Linux BaseOS AUS (v.8.4)Fixed RHSA-2023:5628
Red Hat Enterprise Linux BaseOS E4S (v. 8.1)Fixed RHSA-2023:6799, RHSA-2023:6813
Red Hat Enterprise Linux BaseOS E4S (v. 8.2)Fixed RHSA-2023:7417, RHSA-2023:7434
Red Hat Enterprise Linux BaseOS E4S (v.8.4)Fixed RHSA-2023:5628, RHSA-2023:5775
Red Hat Enterprise Linux BaseOS EUS (v.8.6)Fixed RHSA-2023:7398, RHSA-2023:7410
Red Hat Enterprise Linux BaseOS EUS (v.9.0)Fixed RHSA-2023:7382, RHSA-2023:7411
Red Hat Enterprise Linux BaseOS TUS (v. 8.2)Fixed RHSA-2023:7434
Red Hat Enterprise Linux BaseOS TUS (v.8.4)Fixed RHSA-2023:5628
Red Hat Enterprise Linux CRB (v. 8)Fixed RHSA-2023:5244
Red Hat Enterprise Linux CRB (v. 9)Fixed RHSA-2023:5069
Red Hat Enterprise Linux Client (v. 7)Fixed RHSA-2023:7423
Red Hat Enterprise Linux Client Optional (v. 7)Fixed RHSA-2023:7423
Red Hat Enterprise Linux ComputeNode Optional (v. 7)Fixed RHSA-2023:7423
Red Hat Enterprise Linux NFV (v. 8)Fixed RHSA-2023:5255
Red Hat Enterprise Linux NFV (v. 9)Fixed RHSA-2023:5091
Red Hat Enterprise Linux NFV TUS (v.8.4)Fixed RHSA-2023:5794
Red Hat Enterprise Linux RT (v. 8)Fixed RHSA-2023:5255
Red Hat Enterprise Linux RT (v. 9)Fixed RHSA-2023:5091
Red Hat Enterprise Linux RT TUS (v.8.4)Fixed RHSA-2023:5794
Red Hat Enterprise Linux Real Time EUS (v.9.0)Fixed RHSA-2023:7389
Red Hat Enterprise Linux Real Time TUS (v. 8.2)Fixed RHSA-2023:7431
Red Hat Enterprise Linux Real Time for NFV EUS (v.9.0)Fixed RHSA-2023:7389
Red Hat Enterprise Linux Real Time for NFV TUS (v. 8.2)Fixed RHSA-2023:7431
Red Hat Enterprise Linux Server (v. 6 ELS)Fixed RHSA-2024:1831
Red Hat Enterprise Linux Server (v. 7)Fixed RHSA-2023:7419, RHSA-2023:7423
Red Hat Enterprise Linux Server AUS (v. 7.6)Fixed RHSA-2023:7294
Red Hat Enterprise Linux Server AUS (v. 7.7)Fixed RHSA-2024:0262
Red Hat Enterprise Linux Server Optional (v. 6 ELS)Fixed RHSA-2024:1831
Red Hat Enterprise Linux Server Optional (v. 7)Fixed RHSA-2023:7423
Red Hat Enterprise Linux Server Optional AUS (v. 7.6)Fixed RHSA-2023:7294
Red Hat Enterprise Linux Server Optional AUS (v. 7.7)Fixed RHSA-2024:0262
Red Hat Enterprise Linux Workstation (v. 7)Fixed RHSA-2023:7423
Red Hat Enterprise Linux Workstation Optional (v. 7)Fixed RHSA-2023:7423
Red Hat Enterprise Linux for Real Time (v. 7)Fixed RHSA-2023:7424
Red Hat Enterprise Linux for Real Time for NFV (v. 7)Fixed RHSA-2023:7424
Red Hat Virtualization 4 Hypervisor for RHEL 8Fixed RHSA-2023:7398
Not affected: 1 product
  • Red Hat Enterprise Linux AppStream (v. 9)

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-3776
  2. 2026-10-03 Alias added: GHSA-fcg7-9x44-gx43

References

Patch 2

Advisory 7

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • 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
See all 15278 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences