Skip to main content

W3M CVE-2018-6197

HIGH
NULL Pointer Dereference (CWE-476)
2018-01-25 cve@mitre.org
7.5
CVSS 3.0 · NVD
View

Vulnerability Assessment

Weakness
CWE
OWASP Top 10:2025
A10:2025 - Mishandling of Exceptional Conditions
ASVS 5.0
V16 - Security Logging and Error Handling Null pointer safety, defensive checks
MITRE ATT&CK

1 technique across 1 tactic: Impact

The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up.

Impact

CVSS score of 7.5 (HIGH). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. Public proof-of-concept exploit code is available.

Exploit ScenarioDerived

A remote attacker could crash the application by dereferencing a null pointer by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability.

This Week Schedule remediation this week. Why: HIGH severity (CVSS 7.0-8.9).
Patch available 4.4% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAI

w3m through 0.5.3 is prone to a NULL pointer dereference flaw in formUpdateBuffer in form.c. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Check pointers before dereferencing. Use static analysis tools to detect null pointer paths.

Affects your stack

Find out whether the stacks and servers you run are on an affected version.

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

This vulnerability is classified as NULL Pointer Dereference (CWE-476), which allows attackers to crash the application by dereferencing a null pointer. w3m through 0.5.3 is prone to a NULL pointer dereference flaw in formUpdateBuffer in form.c. Affected products include: Tats W3M, Canonical Ubuntu Linux. Version information: through 0.5.3.

Know when W3M gets its next vulnerability

  • Watch products and get an email when something new is published
  • Check this CVE against your own stack and servers
  • Exploit and PoC references, threat intelligence from 22 sources

No credit card · 7-day full trial

Severity by source

NVD PRIMARY 7.5 HIGH
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

DescriptionNVD

w3m through 0.5.3 is prone to a NULL pointer dereference flaw in formUpdateBuffer in form.c.

Threat Intelligence Overview

EPSS Score
4.4%
Top 10% exploitable
Exploit
POC
Public exploit code exists
Data Quality
3 sources
Confidence: Low

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity HIGH
CISA KEV No
Public POC Yes
EPSS 4.4%
Patch available Yes
Active threat No
Deciding rule
HIGH severity (CVSS 7.0-8.9)
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived
Scheduled
Exploitation· derived
Poc
System Exposure· derived
Open
Automatable· derived
Yes
Human Impact· derived
Medium

Priority Score

62
Low Medium High Critical
KEV: 0
EPSS: +4
CVSS: +38
PoC: +20
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

A null pointer dereference occurs when a program attempts to access memory through a pointer that has been set to NULL (address 0x0).

Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.

Affected Products (CPE)NVD

cpe:2.3:a:tats:w3m:*:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:esm:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:17.10:*:*:*:*:*:*:*

More in W3M

View all
CVE-2022-38223 HIGH POC
7.8 Aug 15

There is an out-of-bounds write in checkType located in etc.c in w3m 0.5.3. Rated high severity (CVSS 7.8), this vulnera

CVE-2018-6196 HIGH POC
7.5 Jan 25

w3m through 0.5.3 is prone to an infinite recursion flaw in HTMLlineproc0 because the feed_table_block_tag function in t

CVE-2023-4255 MEDIUM POC
5.5 Dec 21

An out-of-bounds write issue has been discovered in the backspace handling of the checkType() function in etc.c within t

CVE-2023-38253 MEDIUM POC
5.5 Jul 14

An out-of-bounds read flaw was found in w3m, in the growbuf_to_Str function in indep.c. Rated medium severity (CVSS 5.5)

CVE-2023-38252 MEDIUM POC
5.5 Jul 14

An out-of-bounds read flaw was found in w3m, in the Strnew_size function in Str.c. Rated medium severity (CVSS 5.5), thi

CVE-2016-9428 HIGH
8.8 Dec 12

An issue was discovered in the Tatsuya Kinoshita w3m fork before 0.5.3-31. Rated high severity (CVSS 8.8), this vulnerab

CVE-2016-9425 HIGH
8.8 Dec 12

An issue was discovered in the Tatsuya Kinoshita w3m fork before 0.5.3-31. Rated high severity (CVSS 8.8), this vulnerab

CVE-2016-9423 HIGH
8.8 Dec 12

An issue was discovered in the Tatsuya Kinoshita w3m fork before 0.5.3-31. Rated high severity (CVSS 8.8), this vulnerab

CVE-2016-9422 HIGH
8.8 Dec 12

An issue was discovered in the Tatsuya Kinoshita w3m fork before 0.5.3-31. Rated high severity (CVSS 8.8), this vulnerab

CVE-2016-9424 HIGH
8.8 Dec 12

An issue was discovered in the Tatsuya Kinoshita w3m fork before 0.5.3-31. Rated high severity (CVSS 8.8), this vulnerab

CVE-2016-9426 HIGH
8.8 Dec 12

An issue was discovered in the Tatsuya Kinoshita w3m fork before 0.5.3-31. Rated high severity (CVSS 8.8), this vulnerab

CVE-2016-9429 HIGH
8.8 Dec 12

An issue was discovered in the Tatsuya Kinoshita w3m fork before 0.5.3-31. Rated high severity (CVSS 8.8), this vulnerab

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy