CVE-2021-39360Network attack vector

Information disclosure via missing TLS verification

Published Aug 22, 2021 · Updated Aug 4, 2024

Improper certificate validation in GNOME libzapojit 0.0.3 and earlier allows man-in-the-middle attackers to read OneDrive traffic. The zpj-skydrive.c code creates SoupSessionSync objects without configuring a TLS database, system CA file, or CA file, so server certificates are not verified. An attacker with a network position between an affected client and the OneDrive service can present an invalid certificate and intercept confidential REST API data.

CVSS severity5.9
Medium
EPSS probability0.74%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper certificate validation in GNOME libzapojit 0.0.3 and earlier allows man-in-the-middle attackers to read OneDrive traffic. The zpj-skydrive.c code creates SoupSessionSync objects without configuring a TLS database, system CA file, or CA file, so server certificates are not verified. An attacker with a network position between an affected client and the OneDrive service can present an invalid certificate and intercept confidential REST API data.

The record

CVE
CVE-2021-39360
Published
Aug 22, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-295, T1557
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 22, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.9CanonicalCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-295Improper Certificate Validation
T1557Adversary-in-the-Middle

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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