Skip to content
Noroxi
NVD / CVE Program· CNA GitHub_M

CVE-2025-58369: fs2: Half-shutdown of socket during TLS handshake may result in spin loop on opposite side

Noroxi assessment

Priority: Monitor (action score 21/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.46% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: co.fs2:fs2-io_2.12 (Maven) 3.12.2, 3.13.0-M7, 2.5.13; co.fs2:fs2-io_2.13 (Maven) 3.12.2, 3.13.0-M7, 2.5.13; co.fs2:fs2-io_3 (Maven) 3.12.2, 3.13.0-M7, 2.5.13.

Low priority for now. Upgrade to co.fs2:fs2-io_2.12 (Maven) 3.12.2, 3.13.0-M7, 2.5.13; co.fs2:fs2-io_2.13 (Maven) 3.12.2, 3.13.0-M7, 2.5.13; co.fs2:fs2-io_3 (Maven) 3.12.2, 3.13.0-M7, 2.5.13 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

fs2 is a compositional, streaming I/O library for Scala. Versions up to and including 2.5.12, 3.0.0-M1 through 3.12.2, and 3.13.0-M1 through 3.13.0-M6 are vulnerable to denial of service attacks though TLS sessions using fs2-io on the JVM using the fs2.io.net.tls package. When establishing a TLS session, if one side of the connection shuts down `write` while the peer side is awaiting more data to progress the TLS handshake, the peer side will spin loop on the socket read, fully utilizing a CPU. The CPU is consumed until the overall connection is closed, potentially shutting down a fs2-io powered server. This issue is fixed in versions 2.5.13, 3.12.1, and 3.13.0-M7.

MediumCVSS 5.3 · v3.1—No exploit Fix available
Published
Sep 5, 2025
Updated
Oct 1, 2026
EPSS
0.4% · 40th percentile

Report tools

JSON

Action score

21

Monitor

Low priority for now.

CVSS
21 / 40 · 5.3 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.4%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · GitHub_M
5.3
NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2025-58369

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits instantly.

Your free account also gets you

Running WordPress? Scan your site free with WP Lens

  • Stack alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

Sign up with email · Have an account? Sign in

Free account, no card. Unfollow any time.

Don't want an account? Get "Exploited this week" by email every MondayDon't want an account? RSS feed for typelevel records

Running WordPress? Scan your site free with WP Lens

Is your version affected? Check it

Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

We use this product, ask for help

Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

—

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

  • typelevel fs2

    • >= 3.0.0-M1, < 3.12.2, >= 3.13.0-M1, < 3.13.0-M7, < 2.5.13affected

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Mavenco.fs2:fs2-io_0.26from 0—
Mavenco.fs2:fs2-io_0.27from 0—
Mavenco.fs2:fs2-io_2.11from 0—
Mavenco.fs2:fs2-io_2.12from 3.0.0-M1 · before 3.12.23.12.2
Mavenco.fs2:fs2-io_2.12from 3.13.0-M1 · before 3.13.0-M73.13.0-M7
Mavenco.fs2:fs2-io_2.12before 2.5.132.5.13
Mavenco.fs2:fs2-io_2.12.0-M4from 0—
Mavenco.fs2:fs2-io_2.12.0-M5from 0—
Mavenco.fs2:fs2-io_2.12.0-RC1from 0—
Mavenco.fs2:fs2-io_2.12.0-RC2from 0—
Mavenco.fs2:fs2-io_2.13from 3.0.0-M1 · before 3.12.23.12.2
Mavenco.fs2:fs2-io_2.13from 3.13.0-M1 · before 3.13.0-M73.13.0-M7
Mavenco.fs2:fs2-io_2.13before 2.5.132.5.13
Mavenco.fs2:fs2-io_2.13.0-M5from 0—
Mavenco.fs2:fs2-io_3from 3.0.0-M1 · before 3.12.23.12.2
Mavenco.fs2:fs2-io_3from 3.13.0-M1 · before 3.13.0-M73.13.0-M7
Mavenco.fs2:fs2-io_3before 2.5.132.5.13

Same product

typelevel: all records

Other highest-scoring records for the same primary product.

  • CVE-2022-31183mTLS client verification is skipped in fs2 on Node.js
    39Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Maven:co.fs2:fs2-io_2.122.5.13Package registry (OSV)
Maven:co.fs2:fs2-io_2.123.12.2Package registry (OSV)
Maven:co.fs2:fs2-io_2.123.13.0-M7Package registry (OSV)
Maven:co.fs2:fs2-io_2.132.5.13Package registry (OSV)
Maven:co.fs2:fs2-io_2.133.12.2Package registry (OSV)
Maven:co.fs2:fs2-io_2.133.13.0-M7Package registry (OSV)
Maven:co.fs2:fs2-io_32.5.13Package registry (OSV)
Maven:co.fs2:fs2-io_33.12.2Package registry (OSV)
Maven:co.fs2:fs2-io_33.13.0-M7Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
low · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
Low

Weakness class (CWE)

CWE-400 · Uncontrolled Resource Consumption

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

nvd-secondary

Root cause

Code that parses nested structures sets no depth or size limit. A small input can turn into a disproportionate processing load.

The bug in code

The whole CWE-400 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

ts
function expand(node) {  return node.children.map(expand);}

Fixed

ts
const MAX_DEPTH = 32;function expand(node, depth = 0) {  if (depth > MAX_DEPTH) throw new Error("too deep");  return node.children.map((c) => expand(c, depth + 1));}

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (6 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records