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CVE Record

CVE-2020-29074: scan.c in x11vnc 0.9.16 uses IPC_CREAT|0777 in shmget calls, which allows access by actors other than the c...

scan.c in x11vnc 0.9.16 uses IPC_CREAT|0777 in shmget calls, which allows access by actors other than the current user.

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

x11vnc 0.9.16 created shared-memory areas with permissions that allowed users other than the current user to access them. On shared Linux systems, this could expose or allow interference with data x11vnc places in shared memory. The bundle shows vendor security updates, but no evidence of active exploitation.

Executive priority

Treat this as a targeted hygiene issue, not an internet-wide emergency. Prioritize shared Linux systems using x11vnc because the business risk is unauthorized local access to sensitive remote-desktop runtime data. Patch through normal security maintenance if x11vnc is present.

Technical view

The CVE identifies insecure System V shared-memory creation in x11vnc scan.c: shmget used IPC_CREAT with 0777 permissions. This permits access by other local actors, creating a local confidentiality and integrity concern around x11vnc runtime shared memory. Public fixes are represented by an upstream commit and Debian/Fedora package advisories.

Likely exposure

Exposure is most likely where x11vnc 0.9.16 or affected distro packages run on multi-user Linux systems. Systems with untrusted local users, shared hosting, remote desktop jump hosts, or broad shell access deserve priority review. The provided data does not identify other affected products.

Exploitation context

The source bundle does not show KEV listing or active exploitation evidence. The issue appears local rather than remotely triggerable from the CVE text: another actor must be able to access shared-memory objects on the same system or IPC namespace.

Researcher notes

Evidence is narrow but consistent: the CVE text names x11vnc 0.9.16 and world-accessible shmget permissions, while Debian and Fedora published security updates. No CVSS, CWE, exploit maturity, or broad product matrix is included in the bundle.

Mitigation direction

  • Apply the x11vnc security updates from Debian, Fedora, or the relevant distribution vendor.
  • Upgrade to a build containing the upstream fix for shared-memory permissions.
  • Check vendor guidance for non-Debian and non-Fedora packages before assuming fixed versions.
  • Limit untrusted local user access on hosts running x11vnc until patched.

Validation and detection

  • Inventory hosts for x11vnc 0.9.16 or vulnerable distribution package builds.
  • Confirm installed packages include the Debian, Fedora, or upstream security fix.
  • Review whether x11vnc runs on multi-user systems or shared remote-access servers.
  • Verify local package changelogs reference CVE-2020-29074 or the upstream fix commit.
Prepared
Confidence
medium
Sources
8

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

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CVE-2020-29074 mapping review

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Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
0Timeline events
0ADP providers
7Source links

CVSS and timeline data

No CVSS vectors or timeline events were available in the normalized CVE source material.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
n/an/an/aListed
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.