CVE-2021-47444: drm/edid: In connector_bad_edid() cap num_of_ext by num_blocks read
Vulnerability summary
CVE-2021-47444 is a medium (CVSS 5.5) vulnerability in linux. EPSS estimates a 0.22% chance of exploitation in the next 30 days, higher than 13.2% of scored vulnerabilities.
Not severe (CVSS 5.5, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 7 · Related 7Timeline
- 22-05-2024PublishedVulnerability first disclosed.
- 11-05-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: drm/edid: In connector_bad_edid() cap num_of_ext by num_blocks read In commit e11f5bd8228f ("drm: Add support for DP 1.4 Compliance edid corruption test") the function connector_bad_edid() started assuming that the memory for the EDID passed to it was big enough to hold `edid[0x7e] + 1` blocks of data (1 extra for the base block). It completely ignored the fact that the function was passed `num_blocks` which indicated how much memory had been allocated for the EDID. Let's fix this by adding a bounds check. This is important for handling the case where there's an error in the first block of the EDID. In that case we will call connector_bad_edid() without having re-allocated memory based on `edid[0x7e]`.
CVSS metrics
3 scores · 3 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.22%
Chance of exploitation in the next 30 days
Percentile
13%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.22% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeNo weakness data has been published for this record.
Affected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu62 products
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
- linux-aws-5.13All versions (No fix recorded)
- linux-aws-5.19All versions (No fix recorded)
Linux2 products
- linux≥ e11f5bd8228fc3760c221f940b9f6365dbf3e7ed, < a7b45024f66f9ec769e8dbb1a51ae83cd05929c7 | ≥ e11f5bd8228fc3760c221f940b9f6365dbf3e7ed, < 09f3946bb452918dbfb1982add56f9ffaae393dc | ≥ e11f5bd8228fc3760c221f940b9f6365dbf3e7ed, < 97794170b696856483f74b47bfb6049780d2d3a0 | 5.7
- linux_kernel≥ 5.7, < 5.10.75 | ≥ 5.11, < 5.14.14 | 5.15:rc1 | 5.15:rc2 | 5.15:rc3 | 5.15:rc4 | 5.15:rc5
Debian1 product
- linux< 5.14.16-1
3 vendors · 65 products
