Linux: Double Free
CVE-2023-52679 is a high-severity double 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 26b4d702c44f9e5cf3c5c001ae619a4a001889db, a0a061151a6200c13149dbcdb6c065203c8425d2, d5f490343c77e6708b6c4aa7dbbfbcbb9546adea 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 0.25% 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 26b4d702c44f9e5cf3c5c001ae619a4a001889db or a0a061151a6200c13149dbcdb6c065203c8425d2 or d5f490343c77e6708b6c4aa7dbbfbcbb9546adea or 4541004084527ce9e95a818ebbc4e6b293ffca21, whichever matches your release line, or a later version.
- Update Linux Kernel to 4.19.306 or 5.4.268 or 5.10.209 or 5.15.148, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | bd6f2fd5a1d52198468c5cdc3c2472362dff5aaa up to, but not including, 26b4d702c44f9e5cf3c5c001ae619a4a001889db; bd6f2fd5a1d52198468c5cdc3c2472362dff5aaa up to, but not including, a0a061151a6200c13149dbcdb6c065203c8425d2; bd6f2fd5a1d52198468c5cdc3c2472362dff5aaa up to, but not including, d5f490343c77e6708b6c4aa7dbbfbcbb9546adea; bd6f2fd5a1d52198468c5cdc3c2472362dff5aaa up to, but not including, 4541004084527ce9e95a818ebbc4e6b293ffca21; bd6f2fd5a1d52198468c5cdc3c2472362dff5aaa up to, but not including, b9d760dae5b10e73369b769073525acd7b3be2bd; bd6f2fd5a1d52198468c5cdc3c2472362dff5aaa up to, but not including, b64d09a4e8596f76d27f4b4a90a1cf6baf6a82f8; bd6f2fd5a1d52198468c5cdc3c2472362dff5aaa up to, but not including, cafa992134124e785609a406da4ff2b54052aff7; bd6f2fd5a1d52198468c5cdc3c2472362dff5aaa up to, but not including, 4dde83569832f9377362e50f7748463340c5db6b; and 1 more ranges | 26b4d702c44f9e5cf3c5c001ae619a4a001889db, a0a061151a6200c13149dbcdb6c065203c8425d2, d5f490343c77e6708b6c4aa7dbbfbcbb9546adea, 4541004084527ce9e95a818ebbc4e6b293ffca21, b9d760dae5b10e73369b769073525acd7b3be2bd, b64d09a4e8596f76d27f4b4a90a1cf6baf6a82f8 |
| Linux | Linux Kernel | 4.17 up to, but not including, 4.19.306; 4.20 up to, but not including, 5.4.268; 5.5 up to, but not including, 5.10.209; 5.11 up to, but not including, 5.15.148; 5.16 up to, but not including, 6.1.75; 6.2 up to, but not including, 6.6.14; 6.7 up to, but not including, 6.7.2 | 4.19.306, 5.4.268, 5.10.209, 5.15.148, 6.1.75, 6.6.14 |
| Debian | Debian Linux | 10.0 | Not stated |
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 |
Official description
In the Linux kernel, the following vulnerability has been resolved: of: Fix double free in of_parse_phandle_with_args_map In of_parse_phandle_with_args_map() the inner loop that iterates through the map entries calls of_node_put(new) to free the reference acquired by the previous iteration of the inner loop. This assumes that the value of "new" is NULL on the first iteration of the inner loop. Make sure that this is true in all iterations of the outer loop by setting "new" to NULL after its value is assigned to "cur". Extend the unittest to detect the double free and add an additional test case that actually triggers this path.
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: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- git.kernel.org/stable/c/26b4d702c44f9e5cf3c5c001ae619a4a001889db
- git.kernel.org/stable/c/4541004084527ce9e95a818ebbc4e6b293ffca21
- git.kernel.org/stable/c/4dde83569832f9377362e50f7748463340c5db6b
- git.kernel.org/stable/c/a0a061151a6200c13149dbcdb6c065203c8425d2
- git.kernel.org/stable/c/b64d09a4e8596f76d27f4b4a90a1cf6baf6a82f8
- git.kernel.org/stable/c/b9d760dae5b10e73369b769073525acd7b3be2bd
- git.kernel.org/stable/c/cafa992134124e785609a406da4ff2b54052aff7
- git.kernel.org/stable/c/d5f490343c77e6708b6c4aa7dbbfbcbb9546adea
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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