Linux: Out-of-bounds Read
CVE-2022-49948 is a high-severity out-of-bounds read 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. The record lists versions c555cf04684fde39b5b0dd9fd80730030ee10c4a, e9ba4611ddf676194385506222cce7b0844e708e, f74b4a41c5d7c9522469917e3072e55d435efd9e 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 0.29% 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 c555cf04684fde39b5b0dd9fd80730030ee10c4a or e9ba4611ddf676194385506222cce7b0844e708e or f74b4a41c5d7c9522469917e3072e55d435efd9e or 1cf1930369c9dc428d827b60260c53271bff3285, whichever matches your release line, or a later version.
- Update Linux Kernel to 4.9.328 or 4.14.293 or 4.19.258 or 5.4.213, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | 009e39ae44f4191188aeb6dfbf661b771dbbe515 up to, but not including, c555cf04684fde39b5b0dd9fd80730030ee10c4a; 009e39ae44f4191188aeb6dfbf661b771dbbe515 up to, but not including, e9ba4611ddf676194385506222cce7b0844e708e; 009e39ae44f4191188aeb6dfbf661b771dbbe515 up to, but not including, f74b4a41c5d7c9522469917e3072e55d435efd9e; 009e39ae44f4191188aeb6dfbf661b771dbbe515 up to, but not including, 1cf1930369c9dc428d827b60260c53271bff3285; 009e39ae44f4191188aeb6dfbf661b771dbbe515 up to, but not including, 989201bb8c00b222235aff04e6200230d29dc7bb; 009e39ae44f4191188aeb6dfbf661b771dbbe515 up to, but not including, 2535431ae967ad17585513649625fea7db28d4db; 009e39ae44f4191188aeb6dfbf661b771dbbe515 up to, but not including, c904fe03c4bd1f356a58797d39e2a5d0ca15cefc; 009e39ae44f4191188aeb6dfbf661b771dbbe515 up to, but not including, 566f9c9f89337792070b5a6062dff448b3e7977f; and 17 more ranges | c555cf04684fde39b5b0dd9fd80730030ee10c4a, e9ba4611ddf676194385506222cce7b0844e708e, f74b4a41c5d7c9522469917e3072e55d435efd9e, 1cf1930369c9dc428d827b60260c53271bff3285, 989201bb8c00b222235aff04e6200230d29dc7bb, 2535431ae967ad17585513649625fea7db28d4db |
| Linux | Linux Kernel | before 4.9.328; 4.10 up to, but not including, 4.14.293; 4.15 up to, but not including, 4.19.258; 4.20 up to, but not including, 5.4.213; 5.5 up to, but not including, 5.10.142; 5.11 up to, but not including, 5.15.66; 5.16 up to, but not including, 5.19.8; 6.0 | 4.9.328, 4.14.293, 4.19.258, 5.4.213, 5.10.142, 5.15.66 |
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 | 7.8 | High | CNA |
| CVSS 3.1 | 7.1 | High | NVD |
Official description
In the Linux kernel, the following vulnerability has been resolved: vt: Clear selection before changing the font When changing the console font with ioctl(KDFONTOP) the new font size can be bigger than the previous font. A previous selection may thus now be outside of the new screen size and thus trigger out-of-bounds accesses to graphics memory if the selection is removed in vc_do_resize(). Prevent such out-of-memory accesses by dropping the selection before the various con_font_set() console handlers are called.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Out-of-bounds Read
The product reads data past the end, or before the beginning, of the intended buffer.
How developers prevent this class of flaw
- Use a language that provides appropriate memory abstractions.
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/1cf1930369c9dc428d827b60260c53271bff3285
- git.kernel.org/stable/c/2535431ae967ad17585513649625fea7db28d4db
- git.kernel.org/stable/c/566f9c9f89337792070b5a6062dff448b3e7977f
- git.kernel.org/stable/c/989201bb8c00b222235aff04e6200230d29dc7bb
- git.kernel.org/stable/c/c555cf04684fde39b5b0dd9fd80730030ee10c4a
- git.kernel.org/stable/c/c904fe03c4bd1f356a58797d39e2a5d0ca15cefc
- git.kernel.org/stable/c/e9ba4611ddf676194385506222cce7b0844e708e
- git.kernel.org/stable/c/f74b4a41c5d7c9522469917e3072e55d435efd9e
Recent Out-of-bounds Read vulnerabilities
- 7.5 High severity
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
Spotted an error? Tell us.