CVE•Published 2021-04-17•1 article on news•6 live references•NVD data
CVE-2021-3493
Vulnerability data via CVEDB (Shodan)
CVSS v3.1
8.8
HIGH
EPSS percentile
99
Exploit Prediction Scoring System · top 1% of all CVEs
Description
The overlayfs implementation in the linux kernel did not properly validate with respect to user namespaces the setting of file capabilities on files in an underlying file system. Due to the combination of unprivileged user namespaces along with a patch carried in the Ubuntu kernel to allow unprivileged overlay mounts, an attacker could use this to gain elevated privileges.
Timeline
Published 2021-04-17
External references
Search for exposed instances
Shodan + Censys queries derived from NVD's CPE data. The vuln tag catches assets Shodan has explicitly linked to this CVE; the product / banner fingerprints find exposed instances even when the vuln tag was never applied (which is common).
Shodan · vuln tag304 hosts
vuln:CVE-2021-3493Hosts Shodan has explicitly fingerprinted as vulnerable.
Shodan · OS
os:"Ubuntu Linux"Hosts Shodan identified as running Ubuntu Linux.
More intel sources (5)
Shodan report
vuln:CVE-2021-3493Country / ASN / product breakdown for the vuln query.
Censys
vulnerabilities.cve_id: CVE-2021-3493Censys host search filtered to this CVE id.
grep.app
CVE-2021-3493Public source-code mentions — fast PoC discovery.
GitHub code
CVE-2021-3493GitHub code search for direct mentions.
Google dork
"CVE-2021-3493" exploit -site:nvd.nist.govWrite-ups and news, NVD excluded.
Known PoCs on GitHub (8)
CVE-2021-34938 repos
Mr-xn/Penetration_Testing_POCHTML
渗透测试有关的POC、EXP、脚本、提权、小工具等---About penetration-testing python-script poc getshell csrf xss cms php-getshell domainmod-xss csrf-webshell cobub-razor cve rce sql sql-poc poc-exp bypas…
xairy/linux-kernel-exploitationunknown
A collection of links related to Linux kernel security and exploitation
Threekiii/Awesome-POCJava
一个漏洞 PoC 知识库。A knowledge base for vulnerability PoCs(Proof of Concept), with 1k+ vulnerabilities.
0xsyr0/OSCPPowerShell
OSCP Cheat Sheet
Metarget/metargetPython
Metarget is a framework providing automatic constructions of vulnerable infrastructures.
taielab/awesome-hacking-listsunknown
A curated collection of top-tier penetration testing tools and productivity utilities across multiple domains. Join us to explore, contribute, and enhance your hacking toolkit!
SexyBeast233/SecBooksHTML
安全类各家文库大乱斗
timb-machine/linux-malwareHTML
Tracking interesting Linux (and UNIX) malware. Send PRs