CVE-2021-3156: Baron Samedit
Is CVE-2021-3156 real, exploitable, or a false positive? Here's the community verdict.
signals
public sources
Confirmed exploited in the wild. Patch this first, regardless of the base score.
public exploits
links to sources — we don’t host codeA working exploit is publicly available from a maintained source. Treat this as higher urgency and verify your exposure.
baseline read
auto · not a community verdict
Real — exploited in the wild
CISA confirms active exploitation. Treat scanner hits as true positives unless your specific version or config is unaffected.
Based on CISA KEV
Confirm or dispute →CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Sudo before 1.9.5p2 contains an off-by-one error that can result in a heap-based buffer overflow, which allows privilege escalation to root via "sudoedit -s" and a command-line argument that ends with a single backslash character.
References
Published
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Field notes & remediation
Verdicts are the quick signal. Notes are the evidence and fixes behind them.
- 0
A heap buffer overflow in sudo, reachable through the way sudoedit parses its arguments, gives a local user root. It is local only, so high rather than critical, but sudo is on almost every Unix and Linux system and the exploit works reliably across many distributions, so it is a standard privilege-escalation step once an attacker has any shell.
Who is affected: sudo versions 1.8.2 through 1.8.31p2 and 1.9.0 through 1.9.5p1.
How to check: run
sudo --versionand compare, or run the maintainer's documented test to see whether an unpatched build crashes.Commonly flagged by: Nessus, Qualys, OpenVAS, Trivy.
- 0
Update sudo to 1.9.5p2 or later from your OS vendor. There is no clean workaround, so patching is the fix. After updating, confirm the version and that the known test no longer crashes.
Add a field note or remediationoptional
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