VulnerabilityPublished 15 Apr 2026

CVE-2026-39845: WeblateOrg weblate · Server-Side Request Forgery (SSRF)

Affects WeblateOrg weblateSource CVE Database V5

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Not known to be exploited · CVSS 4.1 Medium : upgrade to 5.17 when convenient.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 3.1 base score

4.1Medium

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 19% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 5.17

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: High
User Interaction: None
Scope: Changed
Confidentiality: Low
Integrity: None
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: High: The attacker is authorized with (i.e., requires) privileges that provide significant (e.g., administrative) control over the vulnerable component that could affect component-wide settings and files.
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: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the impacted component.
Integrity: None: There is no loss of integrity within 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 15 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 30 Oct 2026.

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.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity 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 weblate and weblateorg/weblate to 5.17.

Affected software

Product	Affected	Fixed in
WeblateOrgweblate	Affected <5.17	Fixed in 5.17
GitHubweblateorg/weblate`pkg:github/weblateorg/weblate`Other threats	Affected <5.17	Fixed in 5.17

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Upgrade Weblate to version 5.17 or later, where the SSRF protections in the webhook add-on have been implemented. If immediate upgrade is not possible, disable the webhook add-on to mitigate the vulnerability. Patch status is not explicitly confirmed in vendor advisories, so check the official Weblate release notes or advisories for the latest remediation guidance.

Description

Weblate is a web based localization tool. In versions prior to 5.17, the webhook add-on did not utilize existing SSRF protections. This issue has been fixed in version 5.17. If developers are unable to update immediately, they can disable the webhook add-on as a workaround.

Impact

The vulnerability allows an attacker with high privileges to perform SSRF attacks via the webhook add-on, potentially causing the server to make unintended network requests. The CVSS vector indicates network attack vector, low attack complexity, required privileges, no user interaction, and partial confidentiality impact. There is no impact on integrity or availability reported. No known exploits in the wild have been reported.

Summary

CVE-2026-39845 is a Server-Side Request Forgery (CWE-918) vulnerability affecting Weblate, a web-based localization tool. The vulnerability arises because the webhook add-on in versions before 5.17 did not utilize the SSRF protections present elsewhere in the application. This allows an attacker with high privileges to potentially induce the server to make unintended requests. The issue was addressed in Weblate version 5.17 by applying the necessary SSRF protections to the webhook add-on. No official remediation level or patch links are provided, but upgrading to version 5.17 is the recommended fix. As a temporary workaround, disabling the webhook add-on can mitigate the risk.

CWE-918Server-Side Request Forgery (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.
Implementation · Operation
If there is a known list of applications, IP, hostname, and/or domains to which the product is allowed to communicate, then use allowlists to ensure that outgoing requests are restricted to these known entities. The allowlists could be in the application code or possibly enforced by firewalls or network segmentation.
Implementation · Operation
If the product is expected to be able to connect to arbitrary IP addresses or domains, consider using a denylist that includes private network addresses, internal domain names, etc. The denylist could be in the application code or possibly enforced by firewalls or network segmentation.
Implementation · Input Validation
Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
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 15 Apr 2026, 19:17 UTC

WeaknessesCWE-918

Technical details

References

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