Linux: Missing Release of Memory after Effective Lifetime
CVE-2022-26365 is a high-severity missing release of memory after effective lifetime vulnerability in Linux, with a CVSS 3.1 base score of 7.1 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. There is no confirmed exploitation so far. EPSS estimates a 0.33% 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 Kernel to 4.9.322 or 4.14.287 or 4.19.251 or 5.4.204, whichever matches your release line, or a later version.
- Read the advisory on xenbits.xen.org for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | Not specified in the record | Not stated |
| Xen | xen | Not specified in the record | Not stated |
| Linux | Linux Kernel | 2.6.13 up to, but not including, 4.9.322; 4.14 up to, but not including, 4.14.287; 4.19 up to, but not including, 4.19.251; 5.4 up to, but not including, 5.4.204; 5.10 up to, but not including, 5.10.129; 5.15 up to, but not including, 5.15.53; 5.18 up to, but not including, 5.18.10; 2.6.12; and 1 more ranges | 4.9.322, 4.14.287, 4.19.251, 5.4.204, 5.10.129, 5.15.53 |
| Debian | Debian Linux | 10.0; 11.0 | Not stated |
| Fedora Project | Fedora | 35; 36 | 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
- NoneNothing can be modified.
- 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:N/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.1 | High | NVD |
| CVSS 2.0 | 3.6 | Low | NVD |
Official description
Linux disk/nic frontends data leaks T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Linux Block and Network PV device frontends don't zero memory regions before sharing them with the backend (CVE-2022-26365, CVE-2022-33740). Additionally the granularity of the grant table doesn't allow sharing less than a 4K page, leading to unrelated data residing in the same 4K page as data shared with a backend being accessible by such backend (CVE-2022-33741, CVE-2022-33742).
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Missing Release of Memory after Effective Lifetime
The product does not sufficiently track and release allocated memory after it has been used, making the memory unavailable for reallocation and reuse.
How developers prevent this class of flaw
- Choose a language or tool that provides automatic memory management, or makes manual memory management less error-prone. For example, glibc in Linux provides protection against free of invalid pointers. When using Xcode to target OS X or iOS, enable automatic reference counting (ARC). To help correctly and consistently manage memory when programming in C++, consider using a smart pointer class such as std
- Use an abstraction library to abstract away risky APIs. Not a complete solution.
- Consider using the Boehm-Demers-Weiser garbage collector (bdwgc), which can help avoid leaks.
More Missing Release of Memory after Effective Lifetime vulnerabilities (CWE-401)
Timeline
- CVE record published.
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
- openwall.com/lists/oss-security/2022/07/05/6Mailing List, Third Party Advisory
Third-party and government advisories
- lists.debian.org/debian-lts-announce/2022/10/msg00000.htmlMailing List, Third Party Advisory
- debian.org/security/2022/dsa-5191Third Party Advisory
Other references
Recent Missing Release of Memory after Effective Lifetime vulnerabilities
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
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