CVE-2021-43675Network attack vector

XSS via attacker-controlled albumID error output

Published Dec 15, 2021 · Updated Aug 4, 2024

Cross-site scripting in Lychee-v3 3.2.16 allows remote attackers to execute script in a user's browser through a crafted albumID. php/Access/Guest.php passes the attacker-controlled albumID to exit(), which prints the value directly in an error message without output encoding. A user must open the resulting response; successful exploitation can read or modify browser-accessible data in the Lychee origin.

CVSS severity6.1
Medium
EPSS probability0.85%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in Lychee-v3 3.2.16 allows remote attackers to execute script in a user's browser through a crafted albumID. php/Access/Guest.php passes the attacker-controlled albumID to exit(), which prints the value directly in an error message without output encoding. A user must open the resulting response; successful exploitation can read or modify browser-accessible data in the Lychee origin.

The record

CVE
CVE-2021-43675
Published
Dec 15, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 15, 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

4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:P/A:N
6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/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-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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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