Linux: Double Free
CVE-2026-43414 is a critical-severity double free vulnerability in Linux, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions bb9c7eca6f8f2e4a1cd8ba6711e7efe9044c0327, baabbd29191514391ca81594e43261bd17c6795a, 7172f41786dc08144da4627483e405de57bf8d2c 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 0.6% chance of exploitation within 30 days, which is low compared with other CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Update Linux to bb9c7eca6f8f2e4a1cd8ba6711e7efe9044c0327 or baabbd29191514391ca81594e43261bd17c6795a or 7172f41786dc08144da4627483e405de57bf8d2c or 4097a2afe8acc6038b71aab825430f1403decf20, whichever matches your release line, or a later version.
- Update Linux Kernel to 5.16 or 6.2 or 6.7 or 6.8, whichever matches your release line, or a later version.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 3b9d72442adfbc9ddb0f76dd1b03977b3a578b16 up to, but not including, bb9c7eca6f8f2e4a1cd8ba6711e7efe9044c0327; ef23850940d9a52c39936d27254824ccf5e9b6bd up to, but not including, baabbd29191514391ca81594e43261bd17c6795a; 4895009c4bb72f71f2e682f1e7d2c2d96e482087 up to, but not including, 7172f41786dc08144da4627483e405de57bf8d2c; 4895009c4bb72f71f2e682f1e7d2c2d96e482087 up to, but not including, 4097a2afe8acc6038b71aab825430f1403decf20; 4895009c4bb72f71f2e682f1e7d2c2d96e482087 up to, but not including, d48ea85463f5b34f7b92ea0a13eddf1ab993da7b; 4895009c4bb72f71f2e682f1e7d2c2d96e482087 up to, but not including, c0b7da13a04bd70ef6070bfb9ea85f582294560a; 7861213201838480dc222634c56fb6db113d010d; 6c6bf6cacf9461f8d301cfac4f9c175d80cbcc63; and 12 more ranges | bb9c7eca6f8f2e4a1cd8ba6711e7efe9044c0327, baabbd29191514391ca81594e43261bd17c6795a, 7172f41786dc08144da4627483e405de57bf8d2c, 4097a2afe8acc6038b71aab825430f1403decf20, d48ea85463f5b34f7b92ea0a13eddf1ab993da7b, c0b7da13a04bd70ef6070bfb9ea85f582294560a |
| Linux | Linux Kernel | 5.15.154 up to, but not including, 5.16; 6.1.84 up to, but not including, 6.2; 6.6.24 up to, but not including, 6.7; 6.7.12 up to, but not including, 6.8; 6.8.3 up to, but not including, 6.9; 6.9.1 up to, but not including, 6.19.9; 6.9; 7.0 | 5.16, 6.2, 6.7, 6.8, 6.9, 6.19.9 |
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
- NetworkCan be exploited remotely over a network, including the internet.
- 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:N/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: scsi: qla2xxx: Completely fix fcport double free In qla24xx_els_dcmd_iocb() sp->free is set to qla2x00_els_dcmd_sp_free(). When an error happens, this function is called by qla2x00_sp_release(), when kref_put() releases the first and the last reference. qla2x00_els_dcmd_sp_free() frees fcport by calling qla2x00_free_fcport(). Doing it one more time after kref_put() is a bad idea.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Double Free
The product calls free() twice on the same memory address.
How developers prevent this class of flaw
- Choose a language that provides automatic memory management.
- Ensure that each allocation is freed only once. After freeing a chunk, set the pointer to NULL to ensure the pointer cannot be freed again. In complicated error conditions, be sure that clean-up routines respect the state of allocation properly. If the language is object oriented, ensure that object destructors delete each chunk of memory only once.
- Use a static analysis tool to find double free instances.
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Other references
Recent Double Free vulnerabilities
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 7.8 High severity
- 8.8 High severity
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