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Fencer Intel
high 7.4

CVE-2022-4055 json

When xdg-mail is configured to use thunderbird for mailto URLs, improper parsing of the URL can lead to additional headers being passed to…

published 3y ago modified 4mo ago also EUVD-2022-51432

cvss
7.4
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.7%
EPSS 0.7% chance of exploitation in 30 days, percentile 53%
public exploits
0
none known

Summary

When xdg-mail is configured to use thunderbird for mailto URLs, improper parsing of the URL can lead to additional headers being passed to thunderbird that should not be included per RFC 2368. An attacker can use this method to create a mailto URL that looks safe to users, but will actually attach files when clicked.

Patch / fix

  • xdg-utils RHEL 9 1.1.3-13.el9_6

red hat advisories RHSA-2025:7672

  • xdg-utils AlmaLinux 9 1.1.3-13.el9_6

almalinux advisories ALSA-2025:7672

  • xdg-utils Rocky Linux 9 1.1.3-13.el9_6

rocky linux advisories RLSA-2025:7672

  • xdg-utils Azure Linux 3.0 1.2.1-3

azure linux advisories AZL-37063

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2022-4055 updated cvss 7.4

xdg-utils: improper parse of mailto URIs allows bypass of Thunderbird security mechanism for attachments

  • Red Hat Enterprise Linux 6 xdg-utils Red Hat Enterprise Linux 7 xdg-utils
    affected: workaround, no fix planned “Out of support scope”
  • Red Hat Enterprise Linux 8 xdg-utils
    affected: workaround, no fix planned “Will not fix”
  • Red Hat Enterprise Linux AppStream (v. 9) xdg-utils 1.1.3-13.el9_6
    fixed: vendor fix RHSA-2025:7672

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
last yr.

Exploit prediction

0.69% chance of exploitation in the next 30 days, higher than 53% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • gitlab.freedesktop.org https://gitlab.freedesktop.org/xdg/xdg-utils/-/issues/205#note_1494267 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CISA ADP 3.1 7.4 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N
NVD 3.1 7.4 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N
CNA 3.1 7.4 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N

Affected products

  • n/a xdg-utils

Classification

Weakness
  • CWE-146 Improper Neutralization of Expression/Command Delimiters

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.