CVE-2025-62763VulnerabilityPublished 21 Oct 2025Updated 8 Dec 2025

CVE-2025-62763: Zimbra Collaboration · Server-Side Request Forgery (SSRF)

Affects Zimbra CollaborationSource CVE Database V5

Not known to be exploited · CVSS 5.0 Medium : upgrade to 10.1.12 when convenient.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 3.1 base score

5.0Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.2% chance of exploitation in 30 days – higher than 17% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 10.1.12

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:N

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Changed
Confidentiality: None
Integrity: Low
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Changed: An exploited vulnerability can affect resources beyond the security scope managed by the security authority of the vulnerable component. In this case, the vulnerable component and the impacted component are different and managed by different security authorities.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 21 Oct 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade Zimbra Collaboration to 10.1.12.

Affected software

Product	Affected	Fixed in
Zimbra Collaboration	Affected =0 <10.1.12	Fixed in 10.1.12

AI-suggested

1. Upgrade Zimbra Collaboration Server to version 10.1.12 or later, where the SSRF vulnerability is addressed. 2. Review and harden chat proxy configurations to restrict outbound requests only to trusted endpoints, implementing strict allowlists. 3. Implement network segmentation and firewall rules to limit the server's ability to reach sensitive internal resources. 4. Monitor server logs for unusual outbound request patterns indicative of SSRF exploitation attempts. 5. Employ web application firewalls (WAF) with SSRF detection capabilities to block suspicious requests. 6. Conduct regular security assessments and penetration testing focusing on SSRF vectors within collaboration platforms. 7. Educate administrators and security teams about SSRF risks and ensure timely application of security updates. 8. If immediate upgrade is not feasible, consider disabling or restricting chat proxy features temporarily to reduce attack surface.

Description

Zimbra Collaboration (ZCS) before 10.1.12 allows SSRF because of the configuration of the chat proxy.

Impact

For European organizations, this SSRF vulnerability could lead to unauthorized internal network reconnaissance and manipulation of internal services, potentially compromising business processes and data integrity. While confidentiality and availability are not directly impacted, the ability to send unauthorized requests can facilitate lateral movement, privilege escalation, or indirect data manipulation. Organizations in sectors with strict data integrity requirements, such as finance, healthcare, and government, may face compliance and operational risks. The medium CVSS score reflects moderate risk, but the ease of remote exploitation with low privileges increases the urgency of mitigation. Given the collaborative nature of Zimbra, exploitation could also affect communication workflows, causing indirect operational disruptions. The absence of known exploits reduces immediate risk but does not eliminate the threat, especially as attackers often develop exploits after vulnerability disclosure. European entities with extensive internal network architectures and reliance on Zimbra Collaboration should consider this vulnerability a significant security concern.

CWE-918Server-Side Request Forgery (SSRF) (opens in a new tab)
Base weaknessCWE Top 25 (2025): #22OWASP Top 10 A01:2025: Broken Access Control (opens in a new tab)
The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.
OWASP Cheat Sheets
Server Side Request Forgery Prevention (opens in a new tab)
Unvalidated Redirects and Forwards (opens in a new tab)
Cross Site Scripting Prevention (opens in a new tab)
DOM based XSS Prevention (opens in a new tab)
Authorization (opens in a new tab)
OWASP ASVS 4.0.3
V12.6.1 (opens in a new tab)
V5.2.6 (opens in a new tab)
Attack patterns
Server Side Request Forgery (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 8 Dec 2025, 16:43 UTC

WeaknessesCWE-918

Technical details

References

Community reviews

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