CVE-2021-24288Public exploitNetwork attack vector

Unauthenticated open redirect via subscription redirect parameter

Published May 17, 2021 · Updated Aug 3, 2024

Open redirect in AcyMailing before 7.5.0 allows remote attackers to send victims to attacker-chosen sites through subscription links. The front-end subscription handler accepts GET parameters and uses the unsanitized redirect value as the post-subscription destination. Exploitation requires a victim to follow the crafted link and a unique email address for each attempt; the result is redirection after a subscription request.

CVSS severity6.1
Medium
EPSS probability1.94%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Open redirect in AcyMailing before 7.5.0 allows remote attackers to send victims to attacker-chosen sites through subscription links. The front-end subscription handler accepts GET parameters and uses the unsanitized redirect value as the post-subscription destination. Exploitation requires a victim to follow the crafted link and a unique email address for each attempt; the result is redirection after a subscription request.

The record

CVE
CVE-2021-24288
Published
May 17, 2021
Updated
Aug 3, 2024
Vendor
AcyMailing Newsletter Team
Product
AcyMailing
Classifications
CWE-601
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 17, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=7.5.0 <7.5.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

AcyMailing Newsletter Team · AcyMailingversion=7.5.0 <7.5.0

Published CVSS scores

6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
5.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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 exploitPublished

Weakness, pattern, technique

CWE-601URL Redirection to Untrusted Site ('Open Redirect')

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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