CVE-2020-9484
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When using Apache Tomcat versions 10.0.0-M1 to 10.0.0-M4, 9.0.0.M1 to 9.0.34, 8.5.0 to 8.5.54 and 7.0.0 to 7.0.103 if a) an attacker is able to…
rank 51 = 23 + 18 + 0 + 10 + 0
rank@v1 · this cycle
Someone is already using it
CISA KEV catalog · public proof-of-concept · FIRST EPSS
EPSS 0.56636 · without this subject the record ranks 28
What it costs you if it fires
NVD CVSS base score, then the CNA's own
CVSS 7.0, from NVD · without this subject the record ranks 33
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 51
How much of the world it touches
NVD CPE configurations
20 products in the CPE ranges · without this subject the record ranks 41
Someone else already set the date
CISA KEV remediation due date
no CISA due date · without this subject the record ranks 51
$2.83M = $4.99M incident cost x 1 exposure x 0.56636 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-502, deserialization of untrusted data. The index holds 3288 prior instances of this class, 76 KEV-listed. The nearest of its KEV-listed records are drawn beside this. taxonomy@v1
Running Apache Tomcat? Check your version
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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: Proof-of-concept published · 17 public repositories, 2020-05-19.
- RUNG 1Nothing observed in held sources
- RUNG 2Proof-of-concept published · 17 public repositories2020-05-19receipt
- RUNG 3Exploited in the wild · CISA KEV listed
- RUNG 4Ransomware campaign use known
Affected & Fixed Versions as published
Show all 20 published ranges
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.
What it is stated by the CNA
When using Apache Tomcat versions 10.0.0-M1 to 10.0.0-M4, 9.0.0.M1 to 9.0.34, 8.5.0 to 8.5.54 and 7.0.0 to 7.0.103 if a) an attacker is able to control the contents and name of a file on the server; and b) the server is configured to use the PersistenceManager with a FileStore; and c) the PersistenceManager is configured with sessionAttributeValueClassNameFilter="null" (the default unless a SecurityManager is used) or a sufficiently lax filter to allow the attacker provided object to be deserialized; and d) the attacker knows the relative file path from the storage location used by FileStore to the file the attacker has control over; then, using a specifically crafted request, the attacker w receipt
Read the rest of the CNA's description
ill be able to trigger remote code execution via deserialization of the file under their control. Note that all of conditions a) to d) must be true for the attack to succeed.
NVD's analysis a second authority
- severity
- 7 CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- weakness
- CWE-502
- affected versions
- apache tomcat >= 7.0.0 < 7.0.108; apache tomcat >= 8.5.0 < 8.5.63; apache tomcat >= 9.0.1 < 9.0.43; and 17 more, listed in full below
check it yourself lists.apache.org lists.debian.org lists.apache.org lists.opensuse.org lists.apache.org lists.debian.org +14 morereceipt
Dated events
Movement the material steps
Show all 72 observations
72 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 pattern, elsewhere
This record is one instance of CWE-502, deserialization of untrusted data. The index holds 3288 prior instances of this class, 76 KEV-listed. The nearest of its KEV-listed records are drawn beside this. [email protected]
"Matches n of m" counts the attributes the two records can both be compared on: the CVSS metrics they share a version of, any weakness class beyond this one, and the vendor. fit-rules@v1
3288 records in this class held. The six above are drawn from the ones CISA has listed as exploited, ranked by how much of the record matches this one. That is why every one of them is KEV-listed: the pool is, so the colour on those spokes says nothing the pool has not already said.
No curated product neighbourhood is held for this product, so the records above are the nearest this index can name. The neighbourhood table covers a small set of products and is extended by hand.
Siblings and hubs
Records related to this one
Browse the index from here
These are index-wide views, not findings about CVE-2020-9484.
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.