CVE-2026-46713

Misskey is an open source, federated social media platform. Versions 12.37.0 and later, but prior to 2026.5.4, contain a vulnerability in the JSON-LD signature validation and compaction process that allows spoofed activities to be accepted as valid. This issue has been fixed in version 2026.5.4...

CVE-2026-47746

Misskey is an open source, federated social media platform. Versions 12.37.0 and later, but prior to 2026.5.4, are vulnerable to timing attacks during JSON-LD signature validation and the compaction process. Because the JSON-LD parsing context is not shared between signature verification and...

CVE-2026-47746 Misskey: JSON-LD signature validation + compaction is vulnerable to timing attacks

Misskey is an open source, federated social media platform. Versions 12.37.0 and later, but prior to 2026.5.4, are vulnerable to timing attacks during JSON-LD signature validation and the compaction process. Because the JSON-LD parsing context is not shared between signature verification and...

BIT-MASTODON-2026-48028 Mastodon: Removal of integrity-protected JSON entries from signed activities

Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.5.10, 4.4.17, and 4.3.23, Mastodon's normalization of incoming activities signed with Linked-Data Signatures does not sufficiently protect the activities from a certain class of spoofing, allowing threat actors...

BIT-MASTODON-2026-46349 Mastodon: LD-Signature Bypass via JSON-LD Named-Graph Restructuring

Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.5.10, 4.4.17, and 4.3.23, Mastodon's normalization of incoming activities signed with Linked-Data Signatures does not sufficiently protect the activities from a certain class of spoofing, allowing attackers to...

PYSEC-2026-284 Hyperledger Aries Cloud Agent Python result of presentation verification not checked for LDP-VC

Impact When verifying W3C Format Verifiable Credentials using JSON-LD with Linked Data Proofs LDP-VCs, the result of verifying the presentation document.proof was not factored into the final verified value true/false on the presentation record. Below is an example result from verifying a JSON-LD...

CVE-2026-46349

Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.5.10, 4.4.17, and 4.3.23, Mastodon's normalization of incoming activities signed with Linked-Data Signatures does not sufficiently protect the activities from a certain class of spoofing, allowing attackers to...

CVE-2026-48028

Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.5.10, 4.4.17, and 4.3.23, Mastodon's normalization of incoming activities signed with Linked-Data Signatures does not sufficiently protect the activities from a certain class of spoofing, allowing threat actors...

CVE-2026-50128 Mastodon: Spoofing of attribution domains

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...

CVE-2026-50128

Mastodon vulnerability CVE-2026-50128 affects versions 4.3.0 through 4.5.11 and 4.4.18, where an error in the attributionDomains JSON-LD handling allows an attacker to arbitrarily modify the attributionDomains value on a legitimately signed Update and bypass signature verification. This can under...

CVE-2026-50128

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...

CVE-2026-48028

Mastodon (open-source social network server) versions prior to 4.5.10, 4.4.17, and 4.3.23 are affected. The vulnerability arises from how incoming activities signed with Linked-Data Signatures are normalized, failing to adequately protect against a class of spoofing that lets an attacker remove J...

CVE-2026-48028 Mastodon: Removal of integrity-protected JSON entries from signed activities

Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.5.10, 4.4.17, and 4.3.23, Mastodon's normalization of incoming activities signed with Linked-Data Signatures does not sufficiently protect the activities from a certain class of spoofing, allowing threat actors...

CVE-2026-48028 Mastodon: Removal of integrity-protected JSON entries from signed activities

Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.5.10, 4.4.17, and 4.3.23, Mastodon's normalization of incoming activities signed with Linked-Data Signatures does not sufficiently protect the activities from a certain class of spoofing, allowing threat actors...

CVE-2026-48028

Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.5.10, 4.4.17, and 4.3.23, Mastodon's normalization of incoming activities signed with Linked-Data Signatures does not sufficiently protect the activities from a certain class of spoofing, allowing threat actors...

CVE-2026-46349

Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.5.10, 4.4.17, and 4.3.23, Mastodon's normalization of incoming activities signed with Linked-Data Signatures does not sufficiently protect the activities from a certain class of spoofing, allowing attackers to...

CVE-2026-46349

CVE-2026-46349 affects Mastodon before versions 4.5.10, 4.4.17, and 4.3.23. The issue arises from Mastodon’s normalization of incoming activities signed with Linked-Data Signatures, which does not sufficiently prevent a class of spoofing. An attacker could re-arrange a valid signed JSON-LD activi...

CVE-2026-46349 Mastodon: LD-Signature Bypass via JSON-LD Named-Graph Restructuring

Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.5.10, 4.4.17, and 4.3.23, Mastodon's normalization of incoming activities signed with Linked-Data Signatures does not sufficiently protect the activities from a certain class of spoofing, allowing attackers to...

CVE-2026-46349 Mastodon: LD-Signature Bypass via JSON-LD Named-Graph Restructuring

Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.5.10, 4.4.17, and 4.3.23, Mastodon's normalization of incoming activities signed with Linked-Data Signatures does not sufficiently protect the activities from a certain class of spoofing, allowing attackers to...

PT-2026-52080

Name of the Vulnerable Software and Affected Versions Mastodon versions prior to 4.5.10 Mastodon versions prior to 4.4.17 Mastodon versions prior to 4.3.23 Description Mastodon is a free, open-source social network server based on ActivityPub. The normalization of incoming activities signed with...