CVE-2021-47383 (GCVE-0-2021-47383)
Vulnerability from cvelistv5 – Published: 2024-05-21 15:03 – Updated: 2026-08-05 08:47
VLAI
EPSS
VEX
Title
tty: Fix out-of-bound vmalloc access in imageblit
Summary
In the Linux kernel, the following vulnerability has been resolved:
tty: Fix out-of-bound vmalloc access in imageblit
This issue happens when a userspace program does an ioctl
FBIOPUT_VSCREENINFO passing the fb_var_screeninfo struct
containing only the fields xres, yres, and bits_per_pixel
with values.
If this struct is the same as the previous ioctl, the
vc_resize() detects it and doesn't call the resize_screen(),
leaving the fb_var_screeninfo incomplete. And this leads to
the updatescrollmode() calculates a wrong value to
fbcon_display->vrows, which makes the real_y() return a
wrong value of y, and that value, eventually, causes
the imageblit to access an out-of-bound address value.
To solve this issue I made the resize_screen() be called
even if the screen does not need any resizing, so it will
"fix and fill" the fb_var_screeninfo independently.
Severity
7.8 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-06-17 17:37 UTC
Assigner
References
8 references
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 7e71fcedfda6f7de18f850a6b36e78d78b04476f
(git)
Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 70aed03b1d5a5df974f456cdc8eedb213c94bb8b (git) Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 067c694d06040db6f0c65281bb358452ca6d85b9 (git) Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 8a6a240f52e14356386030d8958ae8b1761d2325 (git) Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 883f7897a25e3ce14a7f274ca4c73f49ac84002a (git) Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < d570c48dd37dbe8fc6875d4461d01a9554ae2560 (git) Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 699d926585daa6ec44be556cdc1ab89e5d54557b (git) Affected: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 , < 3b0c406124719b625b1aba431659f5cdc24a982c (git) |
guessed | |
| Linux | Linux |
Affected:
2.6.12
Unaffected: 0 , < 2.6.12 (semver) Unaffected: 4.4.286 , ≤ 4.4.* (semver) Unaffected: 4.9.285 , ≤ 4.9.* (semver) Unaffected: 4.14.249 , ≤ 4.14.* (semver) Unaffected: 4.19.209 , ≤ 4.19.* (semver) Unaffected: 5.4.151 , ≤ 5.4.* (semver) Unaffected: 5.10.71 , ≤ 5.10.* (semver) Unaffected: 5.14.10 , ≤ 5.14.* (semver) Unaffected: 5.15 , ≤ * (original_commit_for_fix) |
guessed |
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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