letta-ai letta 0.16.4 File URL message_helper.py _convert_message_create_to_message ImageContent server-side request forgery

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.7$0-$5k0.57

Summaryinfo

A vulnerability was found in letta-ai letta 0.16.4. It has been classified as critical. This issue affects the function _convert_message_create_to_message of the file letta/helpers/message_helper.py of the component File URL Handler. Performing a manipulation of the argument ImageContent results in server-side request forgery. This vulnerability is identified as CVE-2026-4964. The attack can be initiated remotely. Additionally, an exploit exists. The vendor was contacted early about this disclosure but did not respond in any way.

Detailsinfo

A vulnerability was found in letta-ai letta 0.16.4. It has been classified as critical. This affects the function _convert_message_create_to_message of the file letta/helpers/message_helper.py of the component File URL Handler. The manipulation of the argument ImageContent with an unknown input leads to a server-side request forgery vulnerability. CWE is classifying the issue as CWE-918. 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. This is going to have an impact on confidentiality, integrity, and availability.

The advisory is shared at gist.github.com. This vulnerability is uniquely identified as CVE-2026-4964. The exploitability is told to be easy. It is possible to initiate the attack remotely. Technical details and a public exploit are known.

The exploit is shared for download at gist.github.com. It is declared as proof-of-concept. The vendor was contacted early about this disclosure but did not respond in any way.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 5.7

VulDB Base Score: 6.3
VulDB Temp Score: 5.7
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Server-side request forgery
CWE: CWE-918
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

03/27/2026 Advisory disclosed
03/27/2026 +0 days VulDB entry created
03/27/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: gist.github.com
Status: Not defined

CVE: CVE-2026-4964 (🔒)
GCVE (CVE): GCVE-0-2026-4964
GCVE (VulDB): GCVE-100-353841
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 03/27/2026 09:28
Changes: 03/27/2026 09:28 (58), 03/27/2026 09:29 (1)
Complete: 🔍
Submitter: Eric-z
Cache ID: 216:424:103

Submitinfo

Accepted

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