🛡️ CVE-2023-53296 on Ubuntu — linux
Description
In the Linux kernel, the following vulnerability has been resolved: sctp: check send stream number after wait_for_sndbuf This patch fixes a corner case where the asoc out stream count may change after wait_for_sndbuf. When the main thread in the client starts a connection, if its out stream count is set to N while the in stream count in the server is set to N - 2, another thread in the client keeps sending the msgs with stream number N - 1, and waits for sndbuf before processing INIT_ACK. However, after processing INIT_ACK, the out stream count in the client is shrunk to N - 2, the same to the in stream count in the server. The crash occurs when the thread waiting for sndbuf is awake and sends the msg in a non-existing stream(N - 1), the call trace is as below: KASAN: null-ptr-deref in range [0x0000000000000038-0x000000000000003f] Call Trace: <TASK> sctp_cmd_send_msg net/sctp/sm_sideeffect.c:1114 [inline] sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1777 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline] sctp_do_sm+0x197d/0x5310 net/sctp/sm_sideeffect.c:1170 sctp_primitive_SEND+0x9f/0xc0 net/sctp/primitive.c:163 sctp_sendmsg_to_asoc+0x10eb/0x1a30 net/sctp/socket.c:1868 sctp_sendmsg+0x8d4/0x1d90 net/sctp/socket.c:2026 inet_sendmsg+0x9d/0xe0 net/ipv4/af_inet.c:825 sock_sendmsg_nosec net/socket.c:722 [inline] sock_sendmsg+0xde/0x190 net/socket.c:745 The fix is to add an unlikely check for the send stream number after the thread wakes up from the wait_for_sndbuf.
Distribution advisory
This page covers CVE-2023-53296 as tracked by Ubuntu, for the package linux. The fix is available in version 5.15.0-79.86; earlier versions remain affected.
How this vulnerability can be exploited
This issue can be reached with local access to the system, attack complexity is low, an attacker needs low-level privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality none, integrity none, availability high.
CVSS metrics in full
The score comes from this vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Attack vector: Local — a local account, shell or session on the host is needed.
- Attack complexity: Low — the attack works reliably, with no preparation.
- Privileges required: Low — an ordinary user account is enough.
- User interaction: None — nobody has to be tricked into anything.
- Scope: Unchanged — the damage stays inside the vulnerable component.
- Confidentiality impact: None.
- Integrity impact: None.
- Availability impact: High — total loss, or loss the attacker controls.
Affected software
UBUNTU-CVE-2023-53296 is recorded against 122 packages.
- linux (fixed in 5.15.0-79.86)
- linux-allwinner-5.19
- linux-aws (fixed in 5.15.0-1042.47)
- linux-aws-5.0
- linux-aws-5.11
- linux-aws-5.13
- linux-aws-5.15 (fixed in 5.15.0-1041.46~20.04.1)
- linux-aws-5.19
- linux-aws-5.3
- linux-aws-5.4 (fixed in 5.4.0-1107.115~18.04.1)
- linux-aws-5.8
- linux-aws-6.2
- linux-aws-6.5
- linux-aws-fips
- linux-aws-hwe
- linux-azure (fixed in 5.15.0-1045.52)
- linux-azure-4.15
- linux-azure-5.11
- linux-azure-5.13
- linux-azure-5.15 (fixed in 5.15.0-1045.52~20.04.1)
- linux-azure-5.19
- linux-azure-5.3
- linux-azure-5.4 (fixed in 5.4.0-1113.119~18.04.1)
- linux-azure-5.8
Show the remaining 98 packages
- linux-azure-6.11
- linux-azure-6.2
- linux-azure-6.5
- linux-azure-edge
- linux-azure-fde
- linux-azure-fde-5.19
- linux-azure-fde-6.2
- linux-azure-fips
- linux-bluefield
- linux-fips
- linux-gcp (fixed in 5.15.0-1039.47)
- linux-gcp-4.15
- linux-gcp-5.11
- linux-gcp-5.13
- linux-gcp-5.15 (fixed in 5.15.0-1039.47~20.04.1)
- linux-gcp-5.19
- linux-gcp-5.3
- linux-gcp-5.4 (fixed in 5.4.0-1110.119~18.04.1)
- linux-gcp-5.8
- linux-gcp-6.11
- linux-gcp-6.2
- linux-gcp-6.5
- linux-gcp-fips
- linux-gke (fixed in 5.15.0-1039.44)
- linux-gke-4.15
- linux-gke-5.15
- linux-gke-5.4
- linux-gkeop (fixed in 5.15.0-1025.30)
- linux-gkeop-5.15
- linux-gkeop-5.4
- linux-hwe
- linux-hwe-5.11
- linux-hwe-5.13
- linux-hwe-5.15 (fixed in 5.15.0-79.86~20.04.2)
- linux-hwe-5.19
- linux-hwe-5.4 (fixed in 5.4.0-156.173~18.04.1)
- linux-hwe-5.8
- linux-hwe-6.11
- linux-hwe-6.2
- linux-hwe-6.5
- linux-hwe-edge
- linux-ibm (fixed in 5.15.0-1035.38)
- linux-ibm-5.15 (fixed in 5.15.0-1036.39~20.04.1)
- linux-ibm-5.4 (fixed in 5.4.0-1054.59~18.04.1)
- linux-intel
- linux-intel-5.13
- linux-intel-iot-realtime (fixed in 5.15.0-1036.38)
- linux-intel-iotg (fixed in 5.15.0-1037.42)
- linux-intel-iotg-5.15 (fixed in 5.15.0-1037.42~20.04.1)
- linux-iot (fixed in 5.4.0-1019.20)
- linux-kvm (fixed in 5.15.0-1039.44)
- linux-lowlatency (fixed in 5.15.0-79.88)
- linux-lowlatency-hwe-5.15 (fixed in 5.15.0-79.88~20.04.1)
- linux-lowlatency-hwe-5.19
- linux-lowlatency-hwe-6.11
- linux-lowlatency-hwe-6.2
- linux-lowlatency-hwe-6.5
- linux-nvidia (fixed in 5.15.0-1030.30)
- linux-nvidia-6.2
- linux-nvidia-6.5
- linux-nvidia-tegra (fixed in 5.15.0-1016.16)
- linux-nvidia-tegra-5.15 (fixed in 5.15.0-1016.16~20.04.1)
- linux-nvidia-tegra-igx (fixed in 5.15.0-1002.2)
- linux-oem
- linux-oem-5.10
- linux-oem-5.13
- linux-oem-5.14
- linux-oem-5.17
- linux-oem-5.6
- linux-oem-6.0
- linux-oem-6.1
- linux-oem-6.11
- linux-oem-6.5
- linux-oem-6.8
- linux-oracle (fixed in 5.15.0-1040.46)
- linux-oracle-5.0
- linux-oracle-5.11
- linux-oracle-5.13
- linux-oracle-5.15 (fixed in 5.15.0-1040.46~20.04.1)
- linux-oracle-5.3
- linux-oracle-5.4 (fixed in 5.4.0-1106.115~18.04.1)
- linux-oracle-5.8
- linux-oracle-6.5
- linux-raspi (fixed in 5.15.0-1035.38)
- linux-raspi-5.4 (fixed in 5.4.0-1091.102~18.04.1)
- linux-raspi-realtime
- linux-raspi2
- linux-realtime
- linux-riscv
- linux-riscv-5.11
- linux-riscv-5.15 (fixed in 5.15.0-1038.42~20.04.2)
- linux-riscv-5.19
- linux-riscv-5.8
- linux-riscv-6.5
- linux-starfive-5.19
- linux-starfive-6.2
- linux-starfive-6.5
- linux-xilinx-zynqmp (fixed in 5.15.0-1025.29)
Timeline and source
Published on 16 September 2025 and last revised on 19 August 2026. No public exploit is currently recorded for this entry. Record sourced from OSV.
References
ubuntu.com (Report)
www.cve.org (Report)
git.kernel.org (Report)
git.kernel.org (Report)
git.kernel.org (Report)
git.kernel.org (Report)
git.kernel.org (Report)
git.kernel.org (Report)
git.kernel.org (Report)
git.kernel.org (Report)
Other advisories for this package
linux has other advisories on record. If you are patching this one, these are worth checking on the same host:
- DEBIAN-CVE-2022-4994 (published 30 Jul 2026)
- CVE-2026-35233 (4.4 Medium, published 1 May 2026)
- CVE-2026-21996 (3.3 Low, published 1 May 2026)
- CVE-2026-21991 (5.5 Medium, published 16 Mar 2026)
- CGA-mcwh-q4vm-9f29 (published 29 Jan 2026)
- CGA-w6xv-3fg4-grm5 (published 29 Jan 2026)
- CGA-8vhr-fq3f-qx7q (published 7 Jan 2026)
- CGA-p49v-mx3v-9ff2 (published 7 Jan 2026)
CVE-2023-53296 on other distributions
Each distribution ships its own build and its own fixed version. Pick the one you run:
Details
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Affected Packages
| Software | From version | Fixed in |
|---|---|---|
| linux | — | 5.15.0-79.86 |
| linux-allwinner-5.19 | — | — |
| linux-aws | — | 5.15.0-1042.47 |
| linux-aws-5.0 | — | — |
| linux-aws-5.11 | — | — |
| linux-aws-5.13 | — | — |
| linux-aws-5.15 | — | 5.15.0-1041.46~20.04.1 |
| linux-aws-5.19 | — | — |
| linux-aws-5.3 | — | — |
| linux-aws-5.4 | — | 5.4.0-1107.115~18.04.1 |
| linux-aws-5.8 | — | — |
| linux-aws-6.2 | — | — |
| linux-aws-6.5 | — | — |
| linux-aws-fips | — | — |
| linux-aws-hwe | — | — |
| linux-azure | — | 5.15.0-1045.52 |
| linux-azure-4.15 | — | — |
| linux-azure-5.11 | — | — |
| linux-azure-5.13 | — | — |
| linux-azure-5.15 | — | 5.15.0-1045.52~20.04.1 |
| linux-azure-5.19 | — | — |
| linux-azure-5.3 | — | — |
| linux-azure-5.4 | — | 5.4.0-1113.119~18.04.1 |
| linux-azure-5.8 | — | — |
| linux-azure-6.11 | — | — |
| linux-azure-6.2 | — | — |
| linux-azure-6.5 | — | — |
| linux-azure-edge | — | — |
| linux-azure-fde | — | — |
| linux-azure-fde-5.19 | — | — |
| linux-azure-fde-6.2 | — | — |
| linux-azure-fips | — | — |
| linux-bluefield | — | — |
| linux-fips | — | — |
| linux-gcp | — | 5.15.0-1039.47 |
| linux-gcp-4.15 | — | — |
| linux-gcp-5.11 | — | — |
| linux-gcp-5.13 | — | — |
| linux-gcp-5.15 | — | 5.15.0-1039.47~20.04.1 |
| linux-gcp-5.19 | — | — |
| linux-gcp-5.3 | — | — |
| linux-gcp-5.4 | — | 5.4.0-1110.119~18.04.1 |
| linux-gcp-5.8 | — | — |
| linux-gcp-6.11 | — | — |
| linux-gcp-6.2 | — | — |
| linux-gcp-6.5 | — | — |
| linux-gcp-fips | — | — |
| linux-gke | — | 5.15.0-1039.44 |
| linux-gke-4.15 | — | — |
| linux-gke-5.15 | — | — |
| linux-gke-5.4 | — | — |
| linux-gkeop | — | 5.15.0-1025.30 |
| linux-gkeop-5.15 | — | — |
| linux-gkeop-5.4 | — | — |
| linux-hwe | — | — |
| linux-hwe-5.11 | — | — |
| linux-hwe-5.13 | — | — |
| linux-hwe-5.15 | — | 5.15.0-79.86~20.04.2 |
| linux-hwe-5.19 | — | — |
| linux-hwe-5.4 | — | 5.4.0-156.173~18.04.1 |
| linux-hwe-5.8 | — | — |
| linux-hwe-6.11 | — | — |
| linux-hwe-6.2 | — | — |
| linux-hwe-6.5 | — | — |
| linux-hwe-edge | — | — |
| linux-ibm | — | 5.15.0-1035.38 |
| linux-ibm-5.15 | — | 5.15.0-1036.39~20.04.1 |
| linux-ibm-5.4 | — | 5.4.0-1054.59~18.04.1 |
| linux-intel | — | — |
| linux-intel-5.13 | — | — |
| linux-intel-iot-realtime | — | 5.15.0-1036.38 |
| linux-intel-iotg | — | 5.15.0-1037.42 |
| linux-intel-iotg-5.15 | — | 5.15.0-1037.42~20.04.1 |
| linux-iot | — | 5.4.0-1019.20 |
| linux-kvm | — | 5.15.0-1039.44 |
| linux-lowlatency | — | 5.15.0-79.88 |
| linux-lowlatency-hwe-5.15 | — | 5.15.0-79.88~20.04.1 |
| linux-lowlatency-hwe-5.19 | — | — |
| linux-lowlatency-hwe-6.11 | — | — |
| linux-lowlatency-hwe-6.2 | — | — |
| linux-lowlatency-hwe-6.5 | — | — |
| linux-nvidia | — | 5.15.0-1030.30 |
| linux-nvidia-6.2 | — | — |
| linux-nvidia-6.5 | — | — |
| linux-nvidia-tegra | — | 5.15.0-1016.16 |
| linux-nvidia-tegra-5.15 | — | 5.15.0-1016.16~20.04.1 |
| linux-nvidia-tegra-igx | — | 5.15.0-1002.2 |
| linux-oem | — | — |
| linux-oem-5.10 | — | — |
| linux-oem-5.13 | — | — |
| linux-oem-5.14 | — | — |
| linux-oem-5.17 | — | — |
| linux-oem-5.6 | — | — |
| linux-oem-6.0 | — | — |
| linux-oem-6.1 | — | — |
| linux-oem-6.11 | — | — |
| linux-oem-6.5 | — | — |
| linux-oem-6.8 | — | — |
| linux-oracle | — | 5.15.0-1040.46 |
| linux-oracle-5.0 | — | — |
| linux-oracle-5.11 | — | — |
| linux-oracle-5.13 | — | — |
| linux-oracle-5.15 | — | 5.15.0-1040.46~20.04.1 |
| linux-oracle-5.3 | — | — |
| linux-oracle-5.4 | — | 5.4.0-1106.115~18.04.1 |
| linux-oracle-5.8 | — | — |
| linux-oracle-6.5 | — | — |
| linux-raspi | — | 5.15.0-1035.38 |
| linux-raspi-5.4 | — | 5.4.0-1091.102~18.04.1 |
| linux-raspi-realtime | — | — |
| linux-raspi2 | — | — |
| linux-realtime | — | — |
| linux-riscv | — | — |
| linux-riscv-5.11 | — | — |
| linux-riscv-5.15 | — | 5.15.0-1038.42~20.04.2 |
| linux-riscv-5.19 | — | — |
| linux-riscv-5.8 | — | — |
| linux-riscv-6.5 | — | — |
| linux-starfive-5.19 | — | — |
| linux-starfive-6.2 | — | — |
| linux-starfive-6.5 | — | — |
| linux-xilinx-zynqmp | — | 5.15.0-1025.29 |
References
Similar Threats
- Unknown CGA-23jx-hhcx-m389
- Unknown CGA-2qp7-6757-fmgc
- Unknown CGA-2rj5-jc55-r267
- Unknown CGA-3m96-cwq8-6xmx
- Unknown CGA-3qj9-973w-fh9g
Vulnerability Monitoring
Track new vulnerabilities in linux
UBUNTU-CVE-2023-53296 is rated CVSS 5.5 Medium. BotEraser monitors your WordPress installation and notifies you when software you use appears in our vulnerability database.
Set Up Free Alerts →No credit card required · Results in minutes
ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.
