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NVD / CVE Program· CNA GitHub_M

CVE-2023-37459: Out-of-bounds read when processing a received IPv6 packet

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.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • No fixed version is recorded, but the references include a patch (commit or PR) link.

Low priority for now. See the fix and affected versions sections below.

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

Contiki-NG is an operating system for internet-of-things devices. In versions 4.9 and prior, when a packet is received, the Contiki-NG network stack attempts to start the periodic TCP timer if it is a TCP packet with the SYN flag set. But the implementation does not first verify that a full TCP header has been received. Specifically, the implementation attempts to access the flags field from the TCP buffer in the following conditional expression in the `check_for_tcp_syn` function. For this reason, an attacker can inject a truncated TCP packet, which will lead to an out-of-bound read from the packet buffer. As of time of publication, a patched version is not available. As a workaround, one can apply the changes in Contiki-NG pull request #2510 to patch the system.

MediumCVSS 5.3 · v3.1—No exploit No fix recorded
Published
Sep 15, 2023
Updated
Jun 17, 2026
EPSS
0.4% · 39th 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
yes
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
5.3
CNA · GitHub_M
5.3
agree

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
  • No fixed version yet

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

Follow CVE-2023-37459

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

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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.

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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.

VendorProduct
contiki-ngcontiki-ng

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • contiki-ng contiki-ngup to 4.9 inclusive

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.

  • contiki-ng contiki-ng

    • <= 4.9affected

Other highest-scoring records for the same primary product.

  • CVE-2020-24336An issue was discovered in Contiki through 3.0 and Contiki-NG through 4.5.
    57Plan
  • CVE-2018-19417An issue was discovered in the MQTT server in Contiki-NG before 4.2.
    42Plan
  • CVE-2018-1000804contiki-ng version 4 contains a Buffer Overflow vulnerability in AQL (Antelope Query Language) database engine that can result in Attacker c
    41Plan

Published before and after this one in the same product

  • ← EarlierCVE-2023-34101Jun 14, 2023 · Contiki-NG vulnerable to out-of-bounds read when processing ICMP DAO input
    36Monitor
  • ← EarlierCVE-2023-37281Sep 15, 2023 · Out-of-bounds read during IPHC address decompression
    21Monitor
  • Later →CVE-2020-27634Oct 10, 2023 · In Contiki 4.5, TCP ISNs are improperly random.
    37Monitor

Remediation

Which version to upgrade to

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

No fix version is recorded for this entry. Check the references for vendor advisories.

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.

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

Weakness class (CWE)

CWE-125 · Out-of-bounds Read

CVSS vector

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

nvd-primary

Attack context

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

ATT&CK techniques

—

Change log

No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.

References

Show all references (1 more)

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

All records