Linux: Use After Free
CVE-2024-26898 is a high-severity use after free vulnerability in Linux, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions ad80c34944d7175fa1f5c7a55066020002921a99, 1a54aa506b3b2f31496731039e49778f54eee881, faf0b4c5e00bb680e8e43ac936df24d3f48c8e65 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 0.31% 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 ad80c34944d7175fa1f5c7a55066020002921a99 or 1a54aa506b3b2f31496731039e49778f54eee881 or faf0b4c5e00bb680e8e43ac936df24d3f48c8e65 or 7dd09fa80b0765ce68bfae92f4e2f395ccf0fba4, whichever matches your release line, or a later version.
- Update linux_kernel to ad80c34944d7 or 1a54aa506b3b or faf0b4c5e00b or 7dd09fa80b07, whichever matches your release line, or a later version.
- Update SIMATIC S7-1500 CPU 1518-4 PN/DP MFP to V3.1.5 or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 7562f876cd93800f2f8c89445f2a563590b24e09 up to, but not including, ad80c34944d7175fa1f5c7a55066020002921a99; 7562f876cd93800f2f8c89445f2a563590b24e09 up to, but not including, 1a54aa506b3b2f31496731039e49778f54eee881; 7562f876cd93800f2f8c89445f2a563590b24e09 up to, but not including, faf0b4c5e00bb680e8e43ac936df24d3f48c8e65; 7562f876cd93800f2f8c89445f2a563590b24e09 up to, but not including, 7dd09fa80b0765ce68bfae92f4e2f395ccf0fba4; 7562f876cd93800f2f8c89445f2a563590b24e09 up to, but not including, 74ca3ef68d2f449bc848c0a814cefc487bf755fa; 7562f876cd93800f2f8c89445f2a563590b24e09 up to, but not including, eb48680b0255a9e8a9bdc93d6a55b11c31262e62; 7562f876cd93800f2f8c89445f2a563590b24e09 up to, but not including, 079cba4f4e307c69878226fdf5228c20aa1c969c; 7562f876cd93800f2f8c89445f2a563590b24e09 up to, but not including, a16fbb80064634b254520a46395e36b87ca4731e; and 2 more ranges | ad80c34944d7175fa1f5c7a55066020002921a99, 1a54aa506b3b2f31496731039e49778f54eee881, faf0b4c5e00bb680e8e43ac936df24d3f48c8e65, 7dd09fa80b0765ce68bfae92f4e2f395ccf0fba4, 74ca3ef68d2f449bc848c0a814cefc487bf755fa, eb48680b0255a9e8a9bdc93d6a55b11c31262e62 |
| Linux | linux_kernel | 2.6.22; 7562f876cd93 up to, but not including, ad80c34944d7; 7562f876cd93 up to, but not including, 1a54aa506b3b; 7562f876cd93 up to, but not including, faf0b4c5e00b; 7562f876cd93 up to, but not including, 7dd09fa80b07; 7562f876cd93 up to, but not including, 74ca3ef68d2f; 7562f876cd93 up to, but not including, eb48680b0255; 7562f876cd93 up to, but not including, 079cba4f4e30; and 2 more ranges | ad80c34944d7, 1a54aa506b3b, faf0b4c5e00b, 7dd09fa80b07, 74ca3ef68d2f, eb48680b0255 |
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP | V3.1.0 up to, but not including, V3.1.5 | V3.1.5 |
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP | V3.1.0 up to, but not including, V3.1.5 | V3.1.5 |
| Siemens | SIMATIC S7-1500 TM MFP - GNU/Linux subsystem | before V1.1.1 | V1.1.1 |
| Siemens | SIPLUS S7-1500 CPU 1518-4 PN/DP MFP | V3.1.0 up to, but not including, V3.1.5 | V3.1.5 |
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
- LocalThe attacker needs local access or must trick a user into running something.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- LowA basic user account is enough.
- 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:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.8 | High | CNA |
| CVSS 3.1 | 7.8 | High | NVD |
| CVSS 3.1 | 7.0 | High | CISA (ADP) |
Official description
In the Linux kernel, the following vulnerability has been resolved: aoe: fix the potential use-after-free problem in aoecmd_cfg_pkts This patch is against CVE-2023-6270. The description of cve is: A flaw was found in the ATA over Ethernet (AoE) driver in the Linux kernel. The aoecmd_cfg_pkts() function improperly updates the refcnt on `struct net_device`, and a use-after-free can be triggered by racing between the free on the struct and the access through the `skbtxq` global queue. This could lead to a denial of service condition or potential code execution. In aoecmd_cfg_pkts(), it always calls dev_put(ifp) when skb initial code is finished. But the net_device ifp will still be used in later tx()->dev_queue_xmit() in kthread. Which means that the dev_put(ifp) should NOT be called in the success path of skb initial code in aoecmd_cfg_pkts(). Otherwise tx() may run into use-after-free because the net_device is freed. This patch removed the dev_put(ifp) in the success path in aoecmd_cfg_pkts(), and added dev_put() after skb xmit in tx().
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
- git.kernel.org/stable/c/079cba4f4e307c69878226fdf5228c20aa1c969c
- git.kernel.org/stable/c/1a54aa506b3b2f31496731039e49778f54eee881
- git.kernel.org/stable/c/74ca3ef68d2f449bc848c0a814cefc487bf755fa
- git.kernel.org/stable/c/7dd09fa80b0765ce68bfae92f4e2f395ccf0fba4
- git.kernel.org/stable/c/a16fbb80064634b254520a46395e36b87ca4731e
- git.kernel.org/stable/c/ad80c34944d7175fa1f5c7a55066020002921a99
- git.kernel.org/stable/c/eb48680b0255a9e8a9bdc93d6a55b11c31262e62
- git.kernel.org/stable/c/f98364e926626c678fb4b9004b75cacf92ff0662
- git.kernel.org/stable/c/faf0b4c5e00bb680e8e43ac936df24d3f48c8e65
Other references
Recent Use After Free vulnerabilities
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.0 High severity
- 7.8 High severity
- 7.8 High severity
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