CVE-2026-54742

Source
https://cve.org/CVERecord?id=CVE-2026-54742
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-54742.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-54742
Aliases
  • GHSA-gwfj-h8r7-792v
Published
2026-08-19T20:10:56.632Z
Modified
2026-08-22T03:30:48.987305886Z
Severity
  • 5.1 (Medium) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N CVSS Calculator
Summary
Lemmy: `CollectionAdd::Featured` does not check the post is in the community
Details

Lemmy is a link aggregator and forum for the fediverse. From 0.19.18 until 0.19.19 and 1.0.0-alpha.20, a community moderator can feature or unfeature posts in other communities through federated CollectionAdd and CollectionRemove activities using CollectionType::Featured. After verifymodaction authorizes the actor against self.community(), the receive handlers in crates/apub/activities/src/community/collectionadd.rs and crates/apub/activities/src/community/collectionremove.rs dereference self.object as an ApubPost and update featuredcommunity without verifying that post.communityid equals community.id. A moderator can therefore target an unrelated post owned by another community, push it into featured feeds and listings, or undo another community's legitimate curation decision. This issue is fixed in versions 0.19.19 and 1.0.0-alpha.20.

Database specific
{
    "cna_assigner": "GitHub_M",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54742.json",
    "cwe_ids": [
        "CWE-863"
    ]
}
References

Affected packages

Git / github.com/lemmynet/lemmy

Affected ranges

Type
GIT
Repo
https://github.com/lemmynet/lemmy
Events
Database specific
Show details
{
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "0.19.19"
        },
        {
            "introduced": "1.0.0-alpha.0"
        },
        {
            "fixed": "1.0.0-alpha.20"
        }
    ],
    "source": [
        "AFFECTED_FIELD",
        "REFERENCES"
    ]
}

Affected versions

0.*
0.10.0
0.10.0-rc.12
0.10.0-rc.13
0.10.0-rc.7
0.10.1
0.10.2
0.11.0
0.11.0-rc.1
0.11.1
0.11.2
0.11.3-rc.4
0.11.4-rc.16
0.12.0
0.12.0-rc.1
0.12.0-rc.2
0.13.0
0.13.0-rc.1
0.13.5-rc.7
0.13.6-rc.2
0.14.0
0.14.0-rc.1
0.14.0-rc.2
0.14.1
0.14.2
0.14.2-rc.1
0.14.3
0.15.0
0.15.0-rc.7
0.15.1
0.16.0
0.16.0-rc.1
0.16.0-rc.2
0.16.0-rc.3
0.16.0-rc.4
0.16.1
0.16.1-rc.1
0.16.2
0.16.2-rc.1
0.16.2-rc.2
0.16.2-rc.3
0.16.3
0.16.3-rc.1
0.16.5
0.17.0
0.17.0-rc.1
0.17.0-rc.3
0.17.0-rc.4
0.17.1
0.18.0
0.18.0-rc.1
0.18.0-rc.2
0.18.0-rc.3
0.18.0-rc.4
0.18.0-rc.5
0.18.0-rc.6
0.18.0-rc.8
0.18.1
0.18.1-rc.1
0.18.1-rc.10
0.18.1-rc.4
0.18.1-rc.9
0.18.4-beta.7
0.19.0
0.19.0-beta.7
0.19.0-rc.1
0.19.0-rc.10
0.19.0-rc.11
0.19.0-rc.12
0.19.0-rc.13
0.19.0-rc.14
0.19.0-rc.15
0.19.0-rc.16
0.19.0-rc.2
0.19.0-rc.3
0.19.0-rc.4
0.19.0-rc.5
0.19.0-rc.6
0.19.0-rc.7
0.19.0-rc.8
0.19.1-rc.1
0.19.1-rc.2
0.19.10
0.19.10-beta.0
0.19.10-beta.1
0.19.10-beta.2
0.19.11
0.19.11-beta.0
0.19.11-beta.1
0.19.11-beta.2
0.19.12
0.19.12-beta.0
0.19.12-beta.1
0.19.12-beta.10
0.19.12-beta.11
0.19.12-beta.12
0.19.12-beta.2
0.19.12-beta.3
0.19.12-beta.4
0.19.12-beta.5
0.19.12-beta.6
0.19.12-beta.7
0.19.12-beta.8
0.19.12-beta.9
0.19.13
0.19.13-beta.1
0.19.14
0.19.14-beta.0
0.19.14-beta.1
0.19.14-beta.2
0.19.15
0.19.15-beta.0
0.19.16
0.19.16-beta.0
0.19.16-beta.1
0.19.17
0.19.17-beta.0
0.19.18
0.19.18-beta.0
0.19.18-beta.1
0.19.18-beta.3
0.19.19
0.19.19-beta.0
0.19.19-beta.1
0.19.2
0.19.2-rc.1
0.19.2-rc.2
0.19.2-rc.4
0.19.2-rc.5
0.19.3
0.19.3-rc.1
0.19.4
0.19.4-beta.1
0.19.4-beta.3
0.19.4-beta.4
0.19.4-beta.5
0.19.4-beta.6
0.19.4-beta.7
0.19.4-beta.8
0.19.4-rc.1
0.19.4-rc.10
0.19.4-rc.11
0.19.4-rc.2
0.19.4-rc.3
0.19.4-rc.4
0.19.4-rc.5
0.19.4-rc.6
0.19.4-rc.7
0.19.4-rc.8
0.19.4-rc.9
0.19.5
0.19.5-alpha.1
0.19.5-alpha.2
0.19.5-alpha.3
0.19.6
0.19.6-beta.14
0.19.6-beta.15
0.19.6-beta.8
0.19.6-beta.9
0.19.7
0.19.7-beta.1
0.19.7-beta.2
0.19.8
0.19.8-beta.0
0.19.9
0.19.9-beta.0
0.19.9-beta.1
0.19.9-beta.2
0.19.9-beta.3
0.19.9-beta.4
0.9.0
0.9.1
0.9.2
0.9.3
0.9.4
0.9.5
0.9.6
0.9.7
0.9.8
0.9.9
1.*
1.0.0-alpha.0
1.0.0-alpha.1
1.0.0-alpha.10
1.0.0-alpha.12
1.0.0-alpha.18
1.0.0-alpha.19
1.0.0-alpha.2
1.0.0-alpha.3
1.0.0-alpha.4
1.0.0-alpha.5
1.0.0-alpha.6
1.0.0-alpha.7
1.0.0-alpha.9
1.0.0-beta.0
v0.*
v0.0.7.4
v0.0.8.1
v0.0.8.2
v0.0.8.3
v0.4.0.3
v0.5.10
v0.7.17
v0.7.18
v0.7.19
v0.7.20
v0.7.21
v0.7.22
v0.7.23
v0.7.24
v0.7.25
v0.7.26
v0.7.28
v0.7.29
v0.7.3
v0.7.30
v0.7.31
v0.7.32
v0.7.33
v0.7.34
v0.7.35
v0.7.36
v0.7.37
v0.7.38
v0.7.39
v0.7.4
v0.7.40
v0.7.41
v0.7.42
v0.7.43
v0.7.44
v0.7.46
v0.7.47
v0.7.48
v0.7.49
v0.7.5
v0.7.50
v0.7.52
v0.7.53
v0.7.54
v0.7.55
v0.7.56
v0.7.57
v0.7.59
v0.7.6
v0.7.61
v0.7.62
v0.7.63
v0.7.64
v0.7.7
v0.7.8
v0.8.0
v0.8.1
v0.8.10
v0.8.3
v0.8.5
v0.8.6
v0.8.7
v0.8.8
v0.8.9

Database specific

source
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-54742.json"