Use-after-free in smb2_is_status_io_timeout()
A use-after-free flaw was found in smb2_is_status_io_timeout() in CIFS in the Linux Kernel. After CIFS transfers response data to a system call, there are still local variable points to the memory region, and if the system call frees it faster than CIFS uses it, CIFS will access a free memory region, leading to a denial of service.
- BDU:2023-01276
- ALSA-2023:7549
- openSUSE-SU-2024:13305-1
- RHSA-2023:7539
- RHSA-2023:7548
- RHSA-2023:7549
- RHSA-2023:7749
- RHSA-2024:0439
- RHSA-2024:0448
- RHSA-2024:0562
- RHSA-2024:0563
- RHSA-2024:1250
- RHSA-2024:1306
- RHSA-2024:2006
- RHSA-2024:2008
- RLSA-2023:7548
- RLSA-2023:7549
- RXSA-2023:7549
- RXSA-2023:7749
- SUSE-SU-2023:3988-1
- Published
- Nov 1, 2023
- Updated
- Jun 17, 2026
- EPSS
- 1.1% · 64th percentile
- CWE
- CWE-416
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Report tools
Action score
26
Monitor
Low priority for now.
- CVSS
- 26 / 40 · 6.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 1.1%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 6.5
- CNA · redhat
- 6.5
- agree
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for the hundreds of thousands of vulnerabilities in the database; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpAffected systems
| Vendor | Product | CPE |
|---|---|---|
| linux | linux kernel | cpe:2.3:o:linux:linux_kernel |
| redhat | enterprise linux | cpe:2.3:o:redhat:enterprise_linux |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- linux linux kernelbefore 6.4
- redhat enterprise linux8.0
- redhat enterprise linux9.0
Versions reported by the vendor
Affected version ranges reported by the assigning authority (redhat). Independent of NVD's CPE analysis and usually ahead of it.
Fedora Fedora
- all versionsaffected
n/a kernel
- all versionsaffected
Red Hat Red Hat Enterprise Linux 6
- all versionsunknown
Red Hat Red Hat Enterprise Linux 7
- all versionsunknown
- all versionsunknown
Red Hat Red Hat Enterprise Linux 8
- all versionsaffected
- all versionsaffected
Red Hat Red Hat Enterprise Linux 9
- all versionsaffected
- all versionsaffected
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
- CVE-2019-13272In the Linux kernel before 5.1.17, ptrace_link in kernel/ptrace.c mishandles the recording of the credentials of a process that wants to creKEV77This week
- CVE-2013-6282The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the v6k and v7 ARM platforms do not validate certain addKEV77This week
- CVE-2013-2094The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9 uses an incorrect integer data type, which allows loKEV77This week
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 |
|---|---|---|
| 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 | 6.1.64-1 · Debian:12 | Package registry (OSV) |
| opensuse:kernel-rt | 5.14.21-150500.13.18.1 · openSUSE:Leap 15.5 | Package registry (OSV) |
| opensuse:kernel-rt_debug | 5.14.21-150500.13.18.1 · openSUSE:Leap 15.5 | Package registry (OSV) |
| opensuse:kernel-source-rt | 5.14.21-150500.13.18.1 · openSUSE:Leap 15.5 | Package registry (OSV) |
| opensuse:kernel-syms-rt | 5.14.21-150500.13.18.1 · openSUSE:Leap 15.5 | Package registry (OSV) |
| red hat:bpftool | 0:4.18.0-477.36.1.el8_8 · Red Hat:rhel_eus:8.8::baseos | Package registry (OSV) |
| red hat:bpftool-debuginfo | 0:4.18.0-477.36.1.el8_8 · Red Hat:rhel_eus:8.8::baseos | Package registry (OSV) |
| red hat:kernel | 0:4.18.0-477.36.1.el8_8 · Red Hat:rhel_eus:8.8::baseos | Package registry (OSV) |
| red hat:kernel-abi-stablelists | 0:4.18.0-477.36.1.el8_8 · Red Hat:rhel_eus:8.8::baseos | Package registry (OSV) |
| red hat:kernel-core | 0:4.18.0-477.36.1.el8_8 · Red Hat:rhel_eus:8.8::baseos | Package registry (OSV) |
| red hat:kernel-debug | 0:4.18.0-477.36.1.el8_8 · Red Hat:rhel_eus:8.8::baseos | Package registry (OSV) |
| red hat:kernel-debug-core | 0:4.18.0-477.36.1.el8_8 · Red Hat:rhel_eus:8.8::baseos | Package registry (OSV) |
| red hat:kernel-debug-debuginfo | 0:4.18.0-477.36.1.el8_8 · Red Hat:rhel_eus:8.8::baseos | Package registry (OSV) |
| red hat:kernel-debug-devel | 0:4.18.0-477.36.1.el8_8 · Red Hat:rhel_eus:8.8::baseos | Package registry (OSV) |
| red hat:kernel-debug-modules | 0:4.18.0-477.36.1.el8_8 · Red Hat:rhel_eus:8.8::baseos | Package registry (OSV) |
| red hat:kernel-debug-modules-extra | 0:4.18.0-477.36.1.el8_8 · Red Hat:rhel_eus:8.8::baseos | Package registry (OSV) |
| red hat:kernel-debuginfo | 0:4.18.0-477.36.1.el8_8 · Red Hat:rhel_eus:8.8::baseos | Package registry (OSV) |
| rocky linux:kernel | 0:4.18.0-513.9.1.el8_9 · Rocky Linux:8 | Package registry (OSV) |
+12
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
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.
No dated events beyond publication.
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.
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).
Technical details
Attack conditions
- Anyone who can reach it over the internet 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
- none
- Integrity
- none
- Availability
- high · the service can be disrupted
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-416 · Use After FreeCVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
nvd-primary
Root cause
After a memory region is freed, another reference pointing to it is still used. By then, the same region may have been allocated for different data.
The bug in code
The whole CWE-416 classA representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.
Vulnerable
free(dev->buf);/* ... another thread is still running ... */process(dev->buf);Fixed
lock(&dev->lock);free(dev->buf);dev->buf = NULL;unlock(&dev->lock);Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- access.redhat.com/security/cve/CVE-2023-1192
- bugzilla.redhat.com/show_bug.cgi?id=2154178
- git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d527f51331cace562393a8038d870b3e9916686f
Vendor advisories and official records. Exploit/PoC links are deliberately left out.