🛡️ CVE-2026-33191 on Ubuntu — linux
Description
Free5GC is an open-source Linux Foundation project for 5th generation (5G) mobile core networks. Versions prior to 1.4.2 are vulnerable to null byte injection in URL path parameters. A remote attacker can inject null bytes (URL-encoded as %00) into the supi path parameter of the UDM's Nudm_SubscriberDataManagement API. This causes URL parsing failure in Go's net/url package with the error "invalid control character in URL", resulting in a 500 Internal Server Error. This null byte injection vulnerability can be exploited for denial of service attacks. When the supi parameter contains null characters, the UDM attempts to construct a URL for UDR that includes these control characters. Go's URL parser rejects them, causing the request to fail with 500 instead of properly validating input and returning 400 Bad Request. This issue has been fixed in version 1.4.2.
Distribution advisory
This page covers CVE-2026-33191 as tracked by Ubuntu, for the package linux. No fixed version has been recorded for this distribution yet.
How this vulnerability can be exploited
This issue can be reached over the network, attack complexity is low, an attacker needs no privileges on the target. No user interaction is required. Rated impact: confidentiality none, integrity none, availability high.
CVSS metrics in full
The score comes from this vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
- Attack vector: Network — reachable from anywhere that can route to the service.
- Attack complexity: Low — the attack works reliably, with no preparation.
- Attack requirements: None — no deployment-specific condition has to hold.
- Privileges required: None — an unauthenticated stranger can try it.
- User interaction: None — nobody has to be tricked into anything.
- Confidentiality impact: None.
- Integrity impact: None.
- Availability impact: High — total loss, or loss the attacker controls.
Weakness class
UBUNTU-CVE-2026-33191 is classified as CWE-158: Improper Neutralization of Null Byte or NUL Character. The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes NUL characters or null bytes when they are sent to a downstream component.
Affected software
UBUNTU-CVE-2026-33191 is recorded against 157 packages.
- linux
- linux-allwinner-5.19
- linux-aws
- linux-aws-5.0
- linux-aws-5.11
- linux-aws-5.13
- linux-aws-5.15
- linux-aws-5.19
- linux-aws-5.3
- linux-aws-5.4
- linux-aws-5.8
- linux-aws-6.14
- linux-aws-6.17
- linux-aws-6.2
- linux-aws-6.5
- linux-aws-6.8
- linux-aws-fips
- linux-aws-hwe
- linux-azure
- linux-azure-4.15
- linux-azure-5.11
- linux-azure-5.13
- linux-azure-5.15
- linux-azure-5.19
Show the remaining 133 packages
- linux-azure-5.3
- linux-azure-5.4
- linux-azure-5.8
- linux-azure-6.11
- linux-azure-6.14
- linux-azure-6.17
- linux-azure-6.2
- linux-azure-6.5
- linux-azure-6.8
- linux-azure-edge
- linux-azure-fde
- linux-azure-fde-5.15
- linux-azure-fde-5.19
- linux-azure-fde-6.14
- linux-azure-fde-6.17
- linux-azure-fde-6.2
- linux-azure-fde-6.8
- linux-azure-fips
- linux-azure-nvidia
- linux-azure-nvidia-6.14
- linux-bluefield
- linux-fips
- linux-gcp
- linux-gcp-4.15
- linux-gcp-5.11
- linux-gcp-5.13
- linux-gcp-5.15
- linux-gcp-5.19
- linux-gcp-5.3
- linux-gcp-5.4
- linux-gcp-5.8
- linux-gcp-6.11
- linux-gcp-6.14
- linux-gcp-6.17
- linux-gcp-6.2
- linux-gcp-6.5
- linux-gcp-6.8
- linux-gcp-fips
- linux-gke
- linux-gke-4.15
- linux-gke-5.15
- linux-gke-5.4
- linux-gkeop
- linux-gkeop-5.15
- linux-gkeop-5.4
- linux-hwe
- linux-hwe-5.11
- linux-hwe-5.13
- linux-hwe-5.15
- linux-hwe-5.19
- linux-hwe-5.4
- linux-hwe-5.8
- linux-hwe-6.11
- linux-hwe-6.14
- linux-hwe-6.17
- linux-hwe-6.2
- linux-hwe-6.5
- linux-hwe-6.8
- linux-hwe-edge
- linux-ibm
- linux-ibm-5.15
- linux-ibm-5.4
- linux-ibm-6.8
- linux-intel-5.13
- linux-intel-iot-realtime
- linux-intel-iotg
- linux-intel-iotg-5.15
- linux-iot
- linux-kvm
- linux-lowlatency
- linux-lowlatency-hwe-5.15
- linux-lowlatency-hwe-5.19
- linux-lowlatency-hwe-6.11
- linux-lowlatency-hwe-6.2
- linux-lowlatency-hwe-6.5
- linux-lowlatency-hwe-6.8
- linux-lts-xenial
- linux-nvidia
- linux-nvidia-6.11
- linux-nvidia-6.2
- linux-nvidia-6.5
- linux-nvidia-6.8
- linux-nvidia-lowlatency
- linux-nvidia-tegra
- linux-nvidia-tegra-5.15
- linux-nvidia-tegra-igx
- 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-6.14
- linux-oem-6.17
- linux-oem-6.5
- linux-oem-6.8
- linux-oracle
- linux-oracle-5.0
- linux-oracle-5.11
- linux-oracle-5.13
- linux-oracle-5.15
- linux-oracle-5.3
- linux-oracle-5.4
- linux-oracle-5.8
- linux-oracle-6.14
- linux-oracle-6.17
- linux-oracle-6.5
- linux-oracle-6.8
- linux-raspi
- linux-raspi-5.4
- linux-raspi-realtime
- linux-raspi2
- linux-realtime
- linux-realtime-6.14
- linux-realtime-6.17
- linux-realtime-6.8
- linux-riscv
- linux-riscv-5.11
- linux-riscv-5.15
- linux-riscv-5.19
- linux-riscv-5.8
- linux-riscv-6.14
- linux-riscv-6.17
- linux-riscv-6.5
- linux-riscv-6.8
- linux-starfive-5.19
- linux-starfive-6.2
- linux-starfive-6.5
- linux-xilinx
- linux-xilinx-zynqmp
Timeline and source
Published on 20 March 2026 and last revised on 24 March 2026. No public exploit is currently recorded for this entry. Record sourced from OSV.
References
ubuntu.com (Report)
www.cve.org (Report)
github.com (Report)
github.com (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-5xvv-94vx-3q3q (published 7 Jan 2026)
- CGA-gmx6-6mf9-9rgq (published 7 Jan 2026)
Same weakness in other software
These advisories are the same class of weakness (CWE-158: Improper Neutralization of Null Byte or NUL Character) in other software:
- CVE-2026-70603 (published 5 Aug 2026)
- CVE-2026-47778 (5.0 Medium, published 30 Jun 2026)
- CVE-2026-41256 (5.5 Medium, published 11 May 2026)
- CVE-2026-43861 (3.7 Low, published 4 May 2026)
- CVE-2026-43859 (3.7 Low, published 4 May 2026)
- CVE-2026-23863 (6.5 Medium, published 1 May 2026)
- CVE-2026-33191 (8.6 High, published 20 Mar 2026)
- CVE-2026-4359 (2.0 Low, published 17 Mar 2026)
CVE-2026-33191 on other distributions
Each distribution ships its own build and its own fixed version. Pick the one you run:
Details
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
Affected Packages
| Software | From version | Fixed in |
|---|---|---|
| linux | — | — |
| linux-allwinner-5.19 | — | — |
| linux-aws | — | — |
| linux-aws-5.0 | — | — |
| linux-aws-5.11 | — | — |
| linux-aws-5.13 | — | — |
| linux-aws-5.15 | — | — |
| linux-aws-5.19 | — | — |
| linux-aws-5.3 | — | — |
| linux-aws-5.4 | — | — |
| linux-aws-5.8 | — | — |
| linux-aws-6.14 | — | — |
| linux-aws-6.17 | — | — |
| linux-aws-6.2 | — | — |
| linux-aws-6.5 | — | — |
| linux-aws-6.8 | — | — |
| linux-aws-fips | — | — |
| linux-aws-hwe | — | — |
| linux-azure | — | — |
| linux-azure-4.15 | — | — |
| linux-azure-5.11 | — | — |
| linux-azure-5.13 | — | — |
| linux-azure-5.15 | — | — |
| linux-azure-5.19 | — | — |
| linux-azure-5.3 | — | — |
| linux-azure-5.4 | — | — |
| linux-azure-5.8 | — | — |
| linux-azure-6.11 | — | — |
| linux-azure-6.14 | — | — |
| linux-azure-6.17 | — | — |
| linux-azure-6.2 | — | — |
| linux-azure-6.5 | — | — |
| linux-azure-6.8 | — | — |
| linux-azure-edge | — | — |
| linux-azure-fde | — | — |
| linux-azure-fde-5.15 | — | — |
| linux-azure-fde-5.19 | — | — |
| linux-azure-fde-6.14 | — | — |
| linux-azure-fde-6.17 | — | — |
| linux-azure-fde-6.2 | — | — |
| linux-azure-fde-6.8 | — | — |
| linux-azure-fips | — | — |
| linux-azure-nvidia | — | — |
| linux-azure-nvidia-6.14 | — | — |
| linux-bluefield | — | — |
| linux-fips | — | — |
| linux-gcp | — | — |
| linux-gcp-4.15 | — | — |
| linux-gcp-5.11 | — | — |
| linux-gcp-5.13 | — | — |
| linux-gcp-5.15 | — | — |
| linux-gcp-5.19 | — | — |
| linux-gcp-5.3 | — | — |
| linux-gcp-5.4 | — | — |
| linux-gcp-5.8 | — | — |
| linux-gcp-6.11 | — | — |
| linux-gcp-6.14 | — | — |
| linux-gcp-6.17 | — | — |
| linux-gcp-6.2 | — | — |
| linux-gcp-6.5 | — | — |
| linux-gcp-6.8 | — | — |
| linux-gcp-fips | — | — |
| linux-gke | — | — |
| linux-gke-4.15 | — | — |
| linux-gke-5.15 | — | — |
| linux-gke-5.4 | — | — |
| linux-gkeop | — | — |
| linux-gkeop-5.15 | — | — |
| linux-gkeop-5.4 | — | — |
| linux-hwe | — | — |
| linux-hwe-5.11 | — | — |
| linux-hwe-5.13 | — | — |
| linux-hwe-5.15 | — | — |
| linux-hwe-5.19 | — | — |
| linux-hwe-5.4 | — | — |
| linux-hwe-5.8 | — | — |
| linux-hwe-6.11 | — | — |
| linux-hwe-6.14 | — | — |
| linux-hwe-6.17 | — | — |
| linux-hwe-6.2 | — | — |
| linux-hwe-6.5 | — | — |
| linux-hwe-6.8 | — | — |
| linux-hwe-edge | — | — |
| linux-ibm | — | — |
| linux-ibm-5.15 | — | — |
| linux-ibm-5.4 | — | — |
| linux-ibm-6.8 | — | — |
| linux-intel-5.13 | — | — |
| linux-intel-iot-realtime | — | — |
| linux-intel-iotg | — | — |
| linux-intel-iotg-5.15 | — | — |
| linux-iot | — | — |
| linux-kvm | — | — |
| linux-lowlatency | — | — |
| linux-lowlatency-hwe-5.15 | — | — |
| linux-lowlatency-hwe-5.19 | — | — |
| linux-lowlatency-hwe-6.11 | — | — |
| linux-lowlatency-hwe-6.2 | — | — |
| linux-lowlatency-hwe-6.5 | — | — |
| linux-lowlatency-hwe-6.8 | — | — |
| linux-lts-xenial | — | — |
| linux-nvidia | — | — |
| linux-nvidia-6.11 | — | — |
| linux-nvidia-6.2 | — | — |
| linux-nvidia-6.5 | — | — |
| linux-nvidia-6.8 | — | — |
| linux-nvidia-lowlatency | — | — |
| linux-nvidia-tegra | — | — |
| linux-nvidia-tegra-5.15 | — | — |
| linux-nvidia-tegra-igx | — | — |
| 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-6.14 | — | — |
| linux-oem-6.17 | — | — |
| linux-oem-6.5 | — | — |
| linux-oem-6.8 | — | — |
| linux-oracle | — | — |
| linux-oracle-5.0 | — | — |
| linux-oracle-5.11 | — | — |
| linux-oracle-5.13 | — | — |
| linux-oracle-5.15 | — | — |
| linux-oracle-5.3 | — | — |
| linux-oracle-5.4 | — | — |
| linux-oracle-5.8 | — | — |
| linux-oracle-6.14 | — | — |
| linux-oracle-6.17 | — | — |
| linux-oracle-6.5 | — | — |
| linux-oracle-6.8 | — | — |
| linux-raspi | — | — |
| linux-raspi-5.4 | — | — |
| linux-raspi-realtime | — | — |
| linux-raspi2 | — | — |
| linux-realtime | — | — |
| linux-realtime-6.14 | — | — |
| linux-realtime-6.17 | — | — |
| linux-realtime-6.8 | — | — |
| linux-riscv | — | — |
| linux-riscv-5.11 | — | — |
| linux-riscv-5.15 | — | — |
| linux-riscv-5.19 | — | — |
| linux-riscv-5.8 | — | — |
| linux-riscv-6.14 | — | — |
| linux-riscv-6.17 | — | — |
| linux-riscv-6.5 | — | — |
| linux-riscv-6.8 | — | — |
| linux-starfive-5.19 | — | — |
| linux-starfive-6.2 | — | — |
| linux-starfive-6.5 | — | — |
| linux-xilinx | — | — |
| linux-xilinx-zynqmp | — | — |
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
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