CVE-2023-2163: Incorrect Verifier Branch Pruning Logic Leads To Arbitrary Read/Write In Linux Kernel and Lateral Privilege Escalation
Noroxi assessment
Priority: Monitor (action score 36/100)
- Public proof-of-concept code exists (GitHub); there is no record of exploitation in the wild.
- Probability of exploitation in the next 30 days: 3.6% (FIRST EPSS); higher than 89.5% of all records.
- Someone with local access to the system can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
- According to CISA the attack is automatable: targets can be found by mass scanning.
- Fixed version: Linux Linux Kernel 71b547f561247897a0a14f3082730156c0533fed.
- Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).
Low priority for now. Upgrade to Linux Linux Kernel 71b547f561247897a0a14f3082730156c0533fed or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
Incorrect verifier pruning in BPF in Linux Kernel >=5.4 leads to unsafe code paths being incorrectly marked as safe, resulting in arbitrary read/write in kernel memory, lateral privilege escalation, and container escape.
- Published
- Sep 20, 2023
- Updated
- Jun 17, 2026
- EPSS
- 3.6% · 89th percentile
- CWE
- CWE-682
Report tools
Action score
36
Monitor
Low priority for now.
- CVSS
- 35 / 40 · 8.8 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 3.6%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 8.8
- CNA · Google
- 10.0
- 1.2 point gap
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- Proof of concept exists, no weaponized module
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| linux | linux kernel | cpe:2.3:o:linux:linux_kernel |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- linux linux kernel5.3 and later · before 5.4.242
- linux linux kernel5.5 and later · before 5.10.179
- linux linux kernel5.11 and later · before 5.15.109
- linux linux kernel5.16 and later · before 6.1.26
- linux linux kernel6.2 and later · before 6.2.13
Versions reported by the vendor
Affected version ranges reported by the assigning authority (Google). Independent of NVD's CPE analysis and usually ahead of it.
Linux Linux Kernel
- before 5.4not affected
- before 71b547f561247897a0a14f3082730156c0533fedaffected · git
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| AlmaLinux:8 | bpftool | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-abi-stablelists | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-core | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-cross-headers | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-debug | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-debug-core | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-debug-devel | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-debug-modules | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-debug-modules-extra | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-devel | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-doc | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-modules | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-modules-extra | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-tools | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-tools-libs | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-tools-libs-devel | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-zfcpdump | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-zfcpdump-core | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-zfcpdump-devel | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-zfcpdump-modules | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | kernel-zfcpdump-modules-extra | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | perf | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
| AlmaLinux:8 | python3-perf | before 4.18.0-513.9.1.el8_9 | 4.18.0-513.9.1.el8_9 |
+96
Same product
linux: all recordsOther highest-scoring records for the same primary product.
- CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV89Now
- CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV85Now
- CVE-2016-5195Race condition in mm/gup.c in the Linux kernel 2.x through 4.x before 4.8.3 allows local users to gain privileges by leveraging incorrect haKEV83Now
Published before and after this one in the same product
- ← EarlierCVE-2023-4155Sep 13, 2023 · Sev-es / sev-snp vmgexit double fetch vulnerability22Monitor
- ← EarlierCVE-2020-36766Sep 18, 2023 · An issue was discovered in the Linux kernel before 5.8.6.13Monitor
- Later →CVE-2023-34319Sep 22, 2023 · Linux: buffer overrun in netback due to unusual packet31Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| Linux Linux Kernel | 71b547f561247897a0a14f3082730156c0533fed | Vendor (CNA) |
| almalinux:bpftool | 4.18.0-513.9.1.el8_9 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel | 4.18.0-513.9.1.el8_9 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-abi-stablelists | 4.18.0-513.9.1.el8_9 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-core | 4.18.0-513.9.1.el8_9 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-cross-headers | 4.18.0-513.9.1.el8_9 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-debug | 4.18.0-513.9.1.el8_9 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-debug-core | 4.18.0-513.9.1.el8_9 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-debug-devel | 4.18.0-513.9.1.el8_9 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-debug-modules | 4.18.0-513.9.1.el8_9 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-debug-modules-extra | 4.18.0-513.9.1.el8_9 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-devel | 4.18.0-513.9.1.el8_9 · AlmaLinux:8 | Package registry (OSV) |
| almalinux:kernel-doc | 4.18.0-513.9.1.el8_9 · AlmaLinux:8 | Package registry (OSV) |
| debian:linux | 6.1.27-1 · Debian:12 | Package registry (OSV) |
| opensuse:dtb-aarch64 | 5.3.18-150300.59.141.1 · openSUSE:Leap 15.4 | Package registry (OSV) |
| opensuse:kernel-64kb | 5.14.21-150500.55.36.1 · openSUSE:Leap 15.5 | Package registry (OSV) |
| opensuse:kernel-azure | 5.14.21-150400.14.72.1 · openSUSE:Leap 15.4 | Package registry (OSV) |
| opensuse:kernel-debug | 5.14.21-150500.55.36.1 · openSUSE:Leap 15.5 | Package registry (OSV) |
| opensuse:kernel-default | 5.14.21-150500.55.36.1 · openSUSE:Leap 15.5 | Package registry (OSV) |
| opensuse:kernel-default-base | 5.14.21-150500.55.36.1.150500.6.15.3 · openSUSE:Leap 15.5 | Package registry (OSV) |
| opensuse:kernel-rt | 5.14.21-150500.13.24.1 · openSUSE:Leap 15.5 | Package registry (OSV) |
| opensuse:kernel-rt_debug | 5.14.21-150500.13.24.1 · openSUSE:Leap 15.5 | Package registry (OSV) |
| opensuse:kernel-source-azure | 5.14.21-150400.14.72.1 · openSUSE:Leap 15.4 | Package registry (OSV) |
| opensuse:kernel-source-rt | 5.14.21-150500.13.24.1 · openSUSE:Leap 15.5 | Package registry (OSV) |
| opensuse:kernel-syms-azure | 5.14.21-150400.14.72.1 · openSUSE:Leap 15.4 | Package registry (OSV) |
| opensuse:kernel-syms-rt | 5.14.21-150500.13.24.1 · openSUSE:Leap 15.5 | Package registry (OSV) |
| red hat:kernel-rt | 0:4.18.0-513.9.1.rt7.311.el8_9 · Red Hat:enterprise_linux:8::nfv | Package registry (OSV) |
| red hat:kernel-rt-core | 0:4.18.0-513.9.1.rt7.311.el8_9 · Red Hat:enterprise_linux:8::nfv | Package registry (OSV) |
| red hat:kernel-rt-debug | 0:4.18.0-513.9.1.rt7.311.el8_9 · Red Hat:enterprise_linux:8::nfv | Package registry (OSV) |
| red hat:kernel-rt-debug-core | 0:4.18.0-513.9.1.rt7.311.el8_9 · Red Hat:enterprise_linux:8::nfv | Package registry (OSV) |
+22
Exploit status
Proof of concept available
A public proof of concept or detection signature exists. Exploit knowledge is out there; don't delay patching.
Evidence
- Proof-of-concept repository on GitHub ×1
Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.
| Source | Kind | Date |
|---|---|---|
| Proof-of-concept repository on GitHub | stars:1 | 2024-11-27 |
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
- Published
- First PoC+434 d
- TodayOct 25, 2026+1132 d
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
National notice (Türkiye Cybersecurity Directorate / USOM)
Official security notices citing this record; remediation advice is on the agency's page.
- TR-23-0509 · Sep 11, 2023(Linux Kernel Güncellemesi)
Technical details
Attack conditions
- Someone with local access to the system can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
Impact can extend beyond the vulnerable component (scope changes).
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Changed
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-682 · Incorrect CalculationCVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
ATT&CK techniques
—
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (1 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.