um: time-travel: fix time corruption
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-787 and the CVSS impact.
Summary
In the Linux kernel, the following vulnerability has been resolved: um: time-travel: fix time corruption In 'basic' time-travel mode (without =inf-cpu or =ext), we still get timer interrupts. These can happen at arbitrary points in time, i.e. while in timer_read(), which pushes time forward just a little bit. Then, if we happen to get the interrupt after calculating the new time to push to, but before actually finishing that, the interrupt will set the time to a value that's incompatible with the forward, and we'll crash because time goes backwards when we do the forwarding. Fix this by reading the time_travel_time, calculating the adjustment, and doing the adjustment all with interrupts disabled.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 5.3 and later | 5.15.149, 6.1.77, 6.6.16, 6.7.4, 6.8 | Patch available | CNA |
- Linux VendorLinux Affected 5.3 and later Fixed in 5.15.149, 6.1.77, 6.6.16, 6.7.4, 6.8 Patch available CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | before 5.15.149; 5.16 to before 6.1.77; 6.2 to before 6.6.16; 6.7 to before 6.7.4 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions before 5.15.149; 5.16 to before 6.1.77; 6.2 to before 6.6.16; 6.7 to before 6.7.4 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 5.15.149, 6.1.77, 6.6.16, 6.7.4, 6.8
Vendor assessments
Red Hat
Red Hat rating: Low. Red Hat's page for this CVE →
Not affected: 4 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2023-52633
- 2026-10-03 Alias added: GHSA-c7h5-f667-cvc5
References
Patch 5
- https://git.kernel.org/stable/c/0c7478a2da3f5fe106b4658338873d50c86ac7ab
- https://git.kernel.org/stable/c/4f7dad73df4cdb2b7042103d3922745d040ad025
- https://git.kernel.org/stable/c/de3e9d8e8d1ae0a4d301109d1ec140796901306c
- https://git.kernel.org/stable/c/b427f55e9d4185f6f17cc1e3296eb8d0c4425283
- https://git.kernel.org/stable/c/abe4eaa8618bb36c2b33e9cdde0499296a23448c
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- 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
Sources
- CVE-2023-52633 · CVE Program
- CVE-2023-52633 · NVD
- FIRST EPSS
- GHSA-c7h5-f667-cvc5 · GitHub Advisory Database · CC BY 4.0
- CVE-2023-52633 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences