CVE-2026-29178Public exploitNetwork attack vector

Unauthenticated SSRF via file_type parameter injection

Published Mar 6, 2026 · Updated Mar 6, 2026

Server-side request forgery in Lemmy before 0.19.16 allows remote attackers to make pict-rs request arbitrary URLs without authentication. The get_image handler directly interpolates the file_type value into a pict-rs processing URL, allowing injected proxy parameters to select a target. The public image endpoint requires no account, and response data from cloud metadata or internal services is streamed back through pict-rs and Lemmy.

CVSS severityUnavailable
Unscored
EPSS probability0.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Server-side request forgery in Lemmy before 0.19.16 allows remote attackers to make pict-rs request arbitrary URLs without authentication. The get_image handler directly interpolates the file_type value into a pict-rs processing URL, allowing injected proxy parameters to select a target. The public image endpoint requires no account, and response data from cloud metadata or internal services is streamed back through pict-rs and Lemmy.

The record

CVE
CVE-2026-29178
Published
Mar 6, 2026
Updated
Mar 6, 2026
Vendor
LemmyNet
Product
Lemmy
Classifications
CWE-918, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 6, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 6, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 0.19.16

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

LemmyNet · Lemmyversion=< 0.19.16

Published CVSS scores

7.7GitHub, Inc.CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-918Server-Side Request Forgery (SSRF)
T1190Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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