Open Redirection in extension "Mail" (mail)
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- Fixed in 4.2.0, 3.12.5
- Who is exposed
- Not reported
Do first: Upgrade to a fixed version: 4.2.0, 3.12.5.
- Exploitation0/40No signal
- Exposure10/25CISA rates it automatable · Data gap: No advisory context yet
- Reach10/20Affects Packagist packages
- Severity5.3/10CVSS 5.3
- No patch0/5No signal
What would change the score
- Would score about 80 if added to CISA KEV
- Would score about 75 if CISA's SSVC rates exploitation active
- Would score about 40 if advisories confirm default setups are exposed
CVE-2026-120327 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 5.3 (medium) and affects Extension "Mail"; fixed in 4.2.0 and 3.12.5.
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- Published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- FIRST's estimate of the chance attackers exploit it in the next 30 days, updated daily.What do these mean? →
- 0.44% · 38th percentile
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 25/100 · provisional
- Fix
- Fixed in 4.2.0, 3.12.5
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: yes
- Technical impact: partial
Summary
The Mail extension for the web-based software platform (Nextcloud) contains a flaw in its click tracking feature that accepts arbitrary destination URLs and redirects users to them. This could allow attackers to craft links on the legitimate website that send users to malicious external sites, potentially enabling phishing or other deception.
Read the original description
The click tracking middleware accepts an arbitrary target URL and redirects to it. Attackers can misuse links to the website to redirect users to external sites.
What to do
Upgrade to a fixed version: 4.2.0, 3.12.5.
Timeline
- CVE published
- First seen by cve.now
- CISA SSVC assessment
Exploitation: none · Automatable: yes · Technical impact: partial
- Record last updated
Affected versions
- mediaessenz/mailPackagist
From 4.0.0 · fixed in 4.2.0; fixed in 3.12.5
Evidence 1
- Advisory
Corrections
None so far.
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Questions about CVE-2026-120327
Is CVE-2026-120327 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
Which versions are affected by CVE-2026-120327?
mediaessenz/mail (Packagist): from 4.0.0 before 4.2.0; before 3.12.5.Source: cve.now feed data
How do I fix CVE-2026-120327?
Upgrade to a fixed version: 4.2.0, 3.12.5.Source: cve.now feed data