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CVE-2026-40042NVD status: Deferred

Pachno: Exposure of File Descriptor to Unintended Control Sphere

CVE-2026-40042 is a critical-severity exposure of file descriptor to unintended control sphere vulnerability in Pachno, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Pachno versions: 1.0.6. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.38% chance of exploitation within 30 days, which is low compared with other CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of Pachno you run against the affected versions below, and install the vendor's latest release.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
PachnoPachno1.0.6Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (vulncheck.com).

Scoring systemScoreSeverityScored by
CVSS 4.09.3CriticalCNA (vulncheck.com)
CVSS 3.19.8CriticalCNA (vulncheck.com)

Official description

Pachno 1.0.6 contains an XML external entity injection vulnerability that allows unauthenticated attackers to read arbitrary files by exploiting unsafe XML parsing in the TextParser helper. Attackers can inject malicious XML entities through wiki table syntax and inline tags in issue descriptions, comments, and wiki articles to trigger entity resolution via simplexml_load_string() without LIBXML_NONET restrictions.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Exposure of File Descriptor to Unintended Control Sphere

A process does not close sensitive file descriptors before invoking a child process, which allows the child to perform unauthorized I/O operations using those descriptors.

More Exposure of File Descriptor to Unintended Control Sphere vulnerabilities (CWE-403)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Pachno

All Pachno vulnerabilities

Recent Exposure of File Descriptor to Unintended Control Sphere vulnerabilities

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