CVE-2021-22600
Double Free: Is CVE-2021-22600 real, exploitable, or a false positive? Here's the community verdict.
Community verdict: No field verdicts yet. Be the first practitioner to weigh in.
signals
public sources
Confirmed exploited in the wild. Patch this first, regardless of the base score.
cisa ssvc
CISA Vulnrichment · assessed
CISA decision, by how critical the affected system is to you:
- low impact → Track
- medium impact → Track
- high impact → Attend
Track: normal patch cycle · Track*: watch closely · Attend: patch sooner · Act: patch now. About SSVC ↗
public exploits
links to sources — we don’t host codeUnverified proof-of-concept code has been published. It may or may not be functional — assess before relying on it.
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:H/PR:L/UI:R/S:C/C:L/I:L/A:H
A double free bug in packet_set_ring() in net/packet/af_packet.c can be exploited by a local user through crafted syscalls to escalate privileges or deny service. We recommend upgrading kernel past the effected versions or rebuilding past ec6af094ea28f0f2dda1a6a33b14cd57e36a9755
References
Published · Added to CISA KEV (75 days after publication)
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timeline
- CISA SSVC assessment · exploitation: active
- Added to CISA KEV · confirmed exploited in the wild
- Added to VulnCheck KEV · reported exploited in the wild
- Published by NVD
Score and exploit changes tracked since .
Community ground truth
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In your experience, is this finding real and exploitable?
awaiting field verdictsCurated baseline: TruePositive's read from public sources is Real & exploitable — a starting point, not a community verdict.
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Field notes & remediation
Verdicts are the quick signal. Notes are the evidence and fixes behind them.
- 0
Linux Kernel Privilege Escalation Vulnerability — Linux Kernel contains a flaw in the packet socket (AF_PACKET) implementation which could lead to incorrectly freeing memory. A local user could exploit this for denial-of-service (DoS) or possibly for privilege escalation. Listed in the CISA KEV catalog (added 2022-04-11) — confirmed exploited in the wild, not theoretical. FIRST EPSS puts the chance of exploitation in the next 30 days at ~7%. Treat it as real and prioritize remediation over triage.
- 0
Required action for Linux Kernel: Apply updates per vendor instructions. CISA set a federal remediation due date of 2022-05-02. After patching, verify the vulnerable path is no longer reachable before closing the finding.
Add a field note or remediationoptional
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