CVE-2021-42940Public exploitNetwork attack vector

Administrator session compromise via unsanitized SVG upload

Published Feb 11, 2022 · Updated Aug 4, 2024

Stored cross-site scripting in Projeqtor 9.3.1 and earlier allows remote authenticated users to execute JavaScript in an administrator's browser. The saveAttachment.php endpoint stores SVG attachments containing external script references without neutralizing their active content. A low-level account must upload the attachment and an administrator must open it; the script then runs with that administrator's application privileges.

CVSS severity9.9
Critical
EPSS probability1.08%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored cross-site scripting in Projeqtor 9.3.1 and earlier allows remote authenticated users to execute JavaScript in an administrator's browser. The saveAttachment.php endpoint stores SVG attachments containing external script references without neutralizing their active content. A low-level account must upload the attachment and an administrator must open it; the script then runs with that administrator's application privileges.

The record

CVE
CVE-2021-42940
Published
Feb 11, 2022
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, T1203
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 11, 2022CVE 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 privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

3.5NIST NVDAV:N/AC:M/Au:S/C:N/I:P/A:N
9.9NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

Public exploit references

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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