CVE-2026-33693

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Source
https://cve.org/CVERecord?id=CVE-2026-33693
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-33693.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-33693
Aliases
Related
Published
2026-03-27T00:03:35.946Z
Modified
2026-04-10T05:43:18.044303Z
Severity
  • 6.5 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N CVSS Calculator
Summary
Lemmy's Activitypub-Federation has SSRF via 0.0.0.0 bypass in activitypub-federation-rust v4_is_invalid()
Details

Lemmy is a link aggregator and forum for the fediverse. Prior to version 0.7.0-beta.9, the v4_is_invalid() function in activitypub-federation-rust (src/utils.rs) does not check for Ipv4Addr::UNSPECIFIED (0.0.0.0). An unauthenticated attacker controlling a remote domain can point it to 0.0.0.0, bypass the SSRF protection introduced by the fix for CVE-2025-25194 (GHSA-7723-35v7-qcxw), and reach localhost services on the target server. Version 0.7.0-beta.9 patches the issue.

Database specific 
{
    "cwe_ids": [
        "CWE-918"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33693.json",
    "cna_assigner": "GitHub_M"
}
References

Affected packages

Git / github.com/lemmynet/activitypub-federation-rust

Affected ranges

Type
GIT
Repo
https://github.com/lemmynet/activitypub-federation-rust
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
5e8e9180038895ad793b7bbe9fd095fa41d48459
Database specific 
{
    "versions": [
        {
            "introduced": "0"
        },
        {
            "fixed": "0.7.0-beta.9"
        }
    ]
}

Affected versions

0.*
0.1.0
0.2.0
0.2.1
0.2.3
0.3.0
0.3.1
0.3.2
0.3.3
0.3.4
0.4.0
0.4.0-rc1
0.4.0-rc2
0.4.0-rc3
0.4.1
0.4.2
0.4.3
0.4.4
0.4.5
0.4.6
0.5.0
0.5.0-beta.1
0.5.0-beta.3
0.5.0-beta.4
0.5.0-beta.5
0.5.0-beta.6
0.5.0-beta.7
0.5.1
0.5.1-beta.1
0.5.2
0.5.3
0.5.4
0.5.5
0.5.6
0.5.7
0.5.8
0.6.0
0.6.0-alpha1
0.6.0-alpha2
0.6.0-alpha3
0.6.1
0.6.2
0.6.3
0.6.4
0.6.5
0.7.0-beta.1
0.7.0-beta.2
0.7.0-beta.3
0.7.0-beta.4
0.7.0-beta.5
0.7.0-beta.6
0.7.0-beta.7
0.7.0-beta.8

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-33693.json"