CVE-2021-30481
Valve Steam before 2021-04-17, when a Source engine game is installed, allows remote authenticated users to execute arbitrary code because of a buffer overflow that occurs for a Steam invite after one
02 Description
Valve Steam before 2021-04-17, when a Source engine game is installed, allows remote authenticated users to execute arbitrary code because of a buffer overflow that occurs for a Steam invite after one
03 Exploitation and scoring
- Exploitation
- Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.
- SSVC decision
- Not assessed by CISA
- EPSS probability
- 3.53% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 89.2% of scored records. A rank, not a probability.
- NVD base score
- 9.0 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H
- NVD analysis status
- Modified. NVD last modified this record on 2026-06-17.
- Red Hat severity
- No Red Hat rating. Red Hat rates the CVEs that affect its products.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2021-04-10 18:31Z5 YR AGO
- Last updated
- 2025-11-03 05:30Z12 MO AGO
- Reserved
- 2021-04-10
- Assigning CNA
- mitre
- Record state
- PUBLISHED
- Severity
- High (CVSS 8.0)
- CNA CVSS vector
- CVSS:3.1/AC:H/AV:N/A:H/C:H/I:H/PR:L/S:C/UI:R
- Weaknesses
- CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')Base
- Data version
- 5.2
- Document digest
- 0138b146692e13fd76f2ad8538b215fdce3b9df7ceaf6a18dca9b020b68e3cc8
05 Affected products
06 References
- twitter.comhttps://twitter.com/the_secret_club/status/1380868759129296900
- www.youtube.comhttps://www.youtube.com/watch?v=rNQn--9xR1Q
- news.ycombinator.comhttps://news.ycombinator.com/item?id=26762170
- twitter.comhttps://twitter.com/floesen_/status/1337107178096881666
07 Fixed in
Arch Linux
- steam Not affected
Source: Arch Linux Security Tracker, the Arch Linux security team. Reformatted by exploit.cc.
A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.