Linux: Use After Free
CVE-2026-64117 is a high-severity use after free vulnerability in Linux, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. The record lists versions 5fe97797412aa8bc0184f78379fafb594bcb7f66, 0cd37e746e98ab0baa6d8b812955220775b080d6, a2650f8461cd8ba287fee2992b36abe733c2bd5e as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.27% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux to 5fe97797412aa8bc0184f78379fafb594bcb7f66 or 0cd37e746e98ab0baa6d8b812955220775b080d6 or a2650f8461cd8ba287fee2992b36abe733c2bd5e or 2fb64f94f9afb774f2fa0c7835727d7a67f89f07, whichever matches your release line, or a later version.
- Update Linux Kernel to 7.0.11 or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 3468e1e0c639032a603450f0830ccabfa76f5806 up to, but not including, 5fe97797412aa8bc0184f78379fafb594bcb7f66; 3468e1e0c639032a603450f0830ccabfa76f5806 up to, but not including, 0cd37e746e98ab0baa6d8b812955220775b080d6; 3468e1e0c639032a603450f0830ccabfa76f5806 up to, but not including, a2650f8461cd8ba287fee2992b36abe733c2bd5e; 3468e1e0c639032a603450f0830ccabfa76f5806 up to, but not including, 2fb64f94f9afb774f2fa0c7835727d7a67f89f07; 3468e1e0c639032a603450f0830ccabfa76f5806 up to, but not including, d71c841be5d9e586ee7f36c0dc8ed4db0d9a1349; 6.4 | 5fe97797412aa8bc0184f78379fafb594bcb7f66, 0cd37e746e98ab0baa6d8b812955220775b080d6, a2650f8461cd8ba287fee2992b36abe733c2bd5e, 2fb64f94f9afb774f2fa0c7835727d7a67f89f07, d71c841be5d9e586ee7f36c0dc8ed4db0d9a1349 |
| Linux | Linux Kernel | 6.4 up to, but not including, 7.0.11; 7.1 | 7.0.11 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- AdjacentThe attacker must be on the same local network segment.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA.
Official description
In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: capture fast-RX rate before mesh reuses skb->cb ieee80211_invoke_fast_rx() reads RX status through IEEE80211_SKB_RXCB(skb), which aliases the same skb->cb storage that ieee80211_rx_mesh_data() reuses as IEEE80211_TX_INFO. In the unicast forward path, mesh_data does: info = IEEE80211_SKB_CB(fwd_skb); memset(info, 0, sizeof(*info)); on the same skb the caller still names via rx->skb, then either queues the skb for TX (success) or kfree_skb()'s it (no-route) before returning RX_QUEUED. The caller's RX_QUEUED arm then calls sta_stats_encode_rate(status) on memory that is either zeroed (success path) or freed (no-route path). The latter is KASAN slab-use-after-free in ieee80211_prepare_and_rx_handle. Fix by encoding the rate from status before invoking ieee80211_rx_mesh_data(), so the RX_QUEUED arm consumes a value captured while status was still backed by valid memory.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Use After Free
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other references
Recent Use After Free vulnerabilities
- 8.8 High severity
- 9.8 Critical severity
- 9.8 Critical severity
- 7.8 High severity
- 9.8 Critical severity
- 8.8 High severity
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