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Vulnerability record · public intelligence
CVE-2020-12826
UNKNOWN

CVE-2020-12826

Published May 12, 2020 · Updated Nov 3, 2026

Severity · CVSSUNKNOWN · Not scored
Known exploitationNot listed
EPSS / likelihood0.71%
QFinch risk scoreNot available

Original summary

Normalized public record · Updated Nov 3, 2026

A signal access-control issue was discovered in the Linux kernel before 5.6.5, aka CID-7395ea4e65c2. Because exec_id in include/linux/sched.h is only 32 bits, an integer overflow can interfere with a do_notify_parent protection mechanism. A child process can send an arbitrary signal to a parent process in a different security domain. Exploitation limitations include the amount of elapsed time before an integer overflow occurs, and the lack of scenarios where signals to a parent process present a substantial operational threat.

Publisher and source text is retained separately from QFinch interpretation.

QFinch assessment

A signal access-control issue was discovered in the Linux kernel before 5.6.5, aka CID-7395ea4e65c2. Because exec_id in include/linux/sched.h is only 32 bits, an integer overflow can interfere with a do_notify_parent protection mechanism. A child process can send an arbitrary signal to a parent process in a different security domain. Exploitation limitations include the amount of elapsed time before an integer overflow occurs, and the lack of scenarios where signals to a parent process present a substantial operational threat.

Evidence: public source records

Affected products

Affected scope reported by the available public evidence
Affected package, product or rangeFix status
Consult the referenced vendor advisory for affected versions.Consult source advisory

Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.

Remediation

Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.

  1. Confirm the affected product and reachable code path exist in your environment.
  2. Apply the vendor-supported patch or mitigation from the primary advisory.
  3. Rescan the exact deployed revision and retain verification evidence.
Review primary references

Evidence coverage

FIRST-EPSSCVE-LIST-V5
SSVC priority
LOW
Confidence
Not available
Aliases
None reported

Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.

Sources and record history

  1. cdn.kernel.org ↗
  2. www.openwall.com ↗
  3. lists.openwall.net ↗
  4. Patch commit ↗
  5. bugzilla.redhat.com ↗
  6. USN-4367-1 ↗
  7. USN-4369-1 ↗
  8. security.netapp.com ↗
  9. [debian-lts-announce] 20200609 [SECURITY] [DLA 2241-1] linux security update ↗
  10. [debian-lts-announce] 20200610 [SECURITY] [DLA 2241-2] linux security update ↗
  11. USN-4391-1 ↗

Record history

Published May 12, 2020 · Last refreshed Nov 3, 2026

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