Buffer overflow in Valvesoftware Steam Client
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 click.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.0 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.035 (88.8th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 89th percentile — 88.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.035 · newest: 0.035 · change: 0.000
Affected products
Weakness classification (CWE)
Public proof-of-concept exploits
References
- twitter.com/the_secret_club/status/1380868759129296900 (Exploit, Third Party Advisory)
- www.youtube.com/watch (Exploit, Third Party Advisory)
- news.ycombinator.com/item (Third Party Advisory, Issue Tracking)
- twitter.com/floesen_/status/1337107178096881666 (Third Party Advisory)
Frequently asked questions
- What is CVE-2021-30481?
- CVE-2021-30481 is a high-severity vulnerability in Valvesoftware Steam Client, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 8.0/10. Published 2021-04-10.
- How severe is CVE-2021-30481?
- High severity. CVSS v3 base score is 8.0 out of 10.
- Is CVE-2021-30481 known to be exploited?
- 13 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.