CVE-2022-31152
No source can show you its own past. This one can.
Print this page to keep the view as it stands on this date. Everything hidden behind a disclosure opens, and every receipt prints with its value.
Synapse vulnerable to denial of service (DoS) due to incorrect application of event authorization rules
rank 21 = 0 + 19 + 0 + 2 + 0
rank@v1 · backlog
Someone is already using it
CISA KEV catalog · public proof-of-concept · FIRST EPSS
EPSS 0.01177 · without this subject the record ranks 21
What it costs you if it fires
NVD CVSS base score, then the CNA's own
CVSS 7.5, from NVD · without this subject the record ranks 2
It is getting worse, not staying still
FIRST EPSS series, rescorings and bad loads removed
no persisting rise in 365 days · without this subject the record ranks 21
How much of the world it touches
NVD CPE configurations
1 product in the CPE ranges · without this subject the record ranks 19
Someone else already set the date
CISA KEV remediation due date
no CISA due date · without this subject the record ranks 21
$47,000 = $4.99M incident cost x 0.8004932139359172 exposure x 0.01177 likelihood
udv@v1 · unaudited · wrong for you until you say what you run
$4.99M is the cost of a breach that happened, from IBM Cost of a Data Breach Report 2026, global average. It is not the value of any asset of yours. That average already covers breaches of every severity, so scaling it by exposure understates a partial-impact record. That is an assumption, not a measurement. Your own asset value goes in the decision record.
Hindsight · the state
Foresight · where to check next
This record is one instance of CWE-703, improper check or handling of exceptional conditions. The index holds 176 prior instances of this class, 3 KEV-listed. taxonomy@v1
Sources disagree here.
Both shown, dated. We don't pick winners. disagreement-rules@v1
Running matrix-org synapse? Check your version
A deterministic range check against the ranges this record publishes. It tells you where a version sits in the record, not whether your deployment is exploitable. No account needed.
Watch this record
Matches your own product list against every record this index holds, and tells you when one of them moves.
Set up a watchlist (needs a Practitioner account)
Record your call
Keep your verdict, your reason and the evidence together. The record takes its date when you save it.
AcceptDeferPatch by…Not affectedMitigatedChoose your verdict, then sign in or use an email link. Your first 100 records are free. Evidence is frozen when the record is created.
Private to your organization unless you share it. Put the proof link in your ticket so a reviewer can inspect the basis for your call. See how decision records work.
Harm, if it fires from the vector and the weakness
Written for the ticket you're about to file.
CISA KEV & Federal Remediation Deadline from the record and CISA
The fix, and how long it's been waiting.
Exploit Status & Known PoCs a ladder, not a score
Current rung: Nothing observed in held sources.
- RUNG 1Nothing observed in held sources
- RUNG 2Proof-of-concept published
- RUNG 3Exploited in the wild · CISA KEV listed
- RUNG 4Ransomware campaign use known
A rung lights from a row in the index, never from an assessment. "Held sources" is the true scope of the claim: this index reads the CVE record, NVD, CISA KEV, FIRST's EPSS and public proof-of-concept repositories, and it does not observe attacks.
Attack path
What it is stated by the CNA
Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. The Matrix specification specifies a list of [event authorization rules](https://spec.matrix.org/v1.2/rooms/v9/#authorization-rules) which must be checked when determining if an event should be accepted into a room. In versions of Synapse up to and including version 1.61.0, some of these rules are not correctly applied. An attacker could craft events which would be accepted by Synapse but not a spec-conformant server, potentially causing divergence in the room state between servers. Administrators of homeservers with federation enabled are advised to upgrade to version 1.62.0 or higher. receipt
Read the rest of the CNA's description
Federation can be disabled by setting [`federation_domain_whitelist`](https://matrix-org.github.io/synapse/latest/usage/configuration/config_documentation.html#federation_domain_whitelist) to an empty list (`[]`) as a workaround.
NVD's analysis a second authority
- severity
- 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- weakness
- CWE-703; CWE-755
- affected versions
- matrix synapse < 1.62.0
- also scored by
- [email protected] 6.4 CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:H
The CNA scored it 6.4 and NVD 7.5. Both are shown because both were published; we do not pick one.
check it yourself github.com github.com github.com github.com receipt
Movement the material steps
Show all 25 observations
25 observations held. A highlighted step crossed a promotion threshold. A step marked with a scoring model moved because the instrument was replaced, not because the vulnerability changed. receipt
The full biography
The record had been public for 4 years when this index was last written.
The pattern, elsewhere
This record is one instance of CWE-703, improper check or handling of exceptional conditions. The index holds 176 prior instances of this class, 3 KEV-listed. [email protected]
176 records in this class held. The six above are ranked by exploit maturity, then recency.
Siblings and hubs
Records related to this one
None. No alias set, and nothing in the corpus cites this identifier or shares its product family within 60 days.
Browse the index from here
These are index-wide views, not findings about CVE-2022-31152.
What usually comes next
Everything above needs no account. What is below is work: assembling it, scoping it to your estate, watching it, and handing it to someone else.