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Threats / Roundcube / CVE-2024-37383
CVE-2024-37383 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Roundcube Webmail vulnerability

Roundcube Webmail contains a cross-site scripting vulnerability in SVG animate attribute handling that allows remote attackers to execute malicious JavaScript.

Verdict

Today item — known-exploited.

A reflected or stored XSS flaw in SVG animation processing enables unauthenticated attackers to inject and execute arbitrary scripts in user browsers, compromising webmail sessions and user data.

CISA KEV Yes · 2024-10-243EPSS 0.73296 (verify live)4Exploit Weaponized · public PoC5
01

Is it exploitable?

— the evidence, ranked above the score
Exploit available
Fully weaponized — public exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
4 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2024-10-24).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.73296 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Roundcube, Webmail. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-79 Cross-site Scripting (XSS) — weakness family: Web / client.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution not established

No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.

03

Why it matters

— the attack path, told twice: adversary, then board
1

Front door — unauthenticated access narrative 1

Attacker
I craft a malicious SVG with animate attributes containing JavaScript payloads.
Business
Webmail users are exposed to account compromise and credential theft through script execution in their browsers.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I deliver the payload via email or web link, triggering script execution when the victim views the message.
Business
Session hijacking and unauthorized access to email accounts result in data exfiltration and reputational damage.
3

Lateral reach — past segmentation narrative 3

Attacker
I harvest session tokens or inject keyloggers to monitor user activity and communications.
Business
Confidentiality and integrity of email communications are compromised, affecting all users relying on the webmail service.
04

What to do

— defensible action
  • Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05

Coverage & confidence

— what we know, and what we don’t

Established (cited)

  • KEV listing (CISA)
  • EPSS probability (FIRST)
  • Weaponized exploit available (VulnCheck)
  • 4 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Public exploit availability
  • Catalogued by mitre (CNA)
  • Coverage gaps — stated, not hidden

  • No EUVD / GCVE mirror in feed — single-authority dependency for the identifier.
  • EPSS & exposure are time-varying; verify live at the source.
  • Threat-actor attribution not established from feed data — absence of a name is not absence of compromise.
  • No finder/reporter credit recorded in the public CVE entry — the work behind this find is unattributed.
  • Disclosure & credit2
    Catalogued by mitreCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.