Skip to content
CVE Ledger
  • Newest CVEsPage
  • Recently added to KEVPage
  • Rising exploitation (EPSS)Page
  • Weekly digestPage
  • StatisticsPage
  • WatchlistPage
  • API docsPage
  • MCP serverPage
  • AboutPage
  • Data sourcesPage
  • Data statusPage
  • ChangelogPage
  • How it's builtPage
  • Support the projectPage

14 results

Back

CVE-2026-50128Mastodon: Spoofing of attribution domains

Description

Mastodon is a free, open-source social network server based on ActivityPub. From 4.3.0 until 4.5.11 and 4.4.18, Mastodon has a feature to let websites credit authors of their articles. To prevent false attribution claims, Mastodon uses the attributionDomains JSON-LD term, however, an error in how it is defined makes Linked Data Signatures on the toot:attributionDomains property ineffective. An attacker can arbitrarily modify the attributionDomains value of a legitimately signed Update activity and bypass Mastodon’s signature verification. This vulnerability is fixed in 4.5.11 and 4.4.18.

Public exploit

An exploit or proof of concept is public: anyone can try it against an unpatched system. A reference of the record is tagged as an exploit.

Show the exploits1

References tagged exploit1 reference

Timeline

  1. ID reserved

    By GitHub_M

  2. · 21 days later

    Published

  3. · 1 day later

    Record updated

Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.

Scores

CVSS scores of CVE-2026-50128, by who scored it
Scored byCVSSScoreVector
GitHub_MCNA (assigner)3.1Medium5.3CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
NVDNVD · Deferred3.1Medium5.3CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
EPSS (exploitation in 30 days)
0.18% · top 92% of all CVEs (15 Nov 2026)
CISA SSVC
Exploitation: none · Automatable: yes · Technical impact: partial
Loading the EPSS history…

The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.3.

Affected products

  • mastodon · mastodon

    • affected >= 4.5.0-beta.1, < 4.5.11
    • affected >= 4.3.0, < 4.4.18

References

References2

Sources

The same CVE in the primary databases and aggregators, to check against.

Badge for a README or a ticket

CVE-2026-50128 badge
[![CVE-2026-50128](https://cveledger.app/badge/CVE-2026-50128.svg)](https://cveledger.app/cve/CVE-2026-50128)

Record last updated .