W^X
E590637
W^X is a memory protection security mechanism that enforces pages to be either writable or executable, but not both, to mitigate exploits such as buffer overflows.
All labels observed (2)
| Label | Occurrences |
|---|---|
| W^X canonical | 1 |
| W^X policy | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T6408972 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: W^X Context triple: [NetBSD, supportsSecurityFeature, W^X]
-
A.
XSWX
XSWX is the Market Identifier Code for the SIX Swiss Exchange, Switzerland’s principal stock exchange based in Zurich.
-
B.
And X
And X is a dwarf spheroidal satellite galaxy of the Andromeda Galaxy (M31) located in the Local Group.
-
C.
OX
OX is the postcode area covering Oxford and its surrounding region in Oxfordshire, England.
-
D.
l’X
l’X is the traditional nickname of École Polytechnique, France’s elite engineering grande école renowned for its rigorous scientific education and prestigious alumni.
-
E.
The W
The W is the commonly used nickname for Mississippi University for Women, a public university in Columbus, Mississippi.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: W^X Target entity description: W^X is a memory protection security mechanism that enforces pages to be either writable or executable, but not both, to mitigate exploits such as buffer overflows.
-
A.
XSWX
XSWX is the Market Identifier Code for the SIX Swiss Exchange, Switzerland’s principal stock exchange based in Zurich.
-
B.
And X
And X is a dwarf spheroidal satellite galaxy of the Andromeda Galaxy (M31) located in the Local Group.
-
C.
OX
OX is the postcode area covering Oxford and its surrounding region in Oxfordshire, England.
-
D.
l’X
l’X is the traditional nickname of École Polytechnique, France’s elite engineering grande école renowned for its rigorous scientific education and prestigious alumni.
-
E.
The W
The W is the commonly used nickname for Mississippi University for Women, a public university in Columbus, Mississippi.
- F. None of above. chosen
Statements (50)
| Predicate | Object |
|---|---|
| instanceOf |
memory protection mechanism
ⓘ
security feature ⓘ |
| affects |
JIT compiler design
ⓘ
dynamic code generation strategies ⓘ |
| alsoKnownAs |
Write XOR Execute policy
ⓘ
W⊕X ⓘ |
| appliesOn |
code segments
ⓘ
heap memory regions ⓘ stack memory regions ⓘ |
| appliesTo | memory pages ⓘ |
| category |
computer security
ⓘ
operating system security ⓘ |
| constrains | page permissions ⓘ |
| contrastsWith | W+X (writable and executable memory) ⓘ |
| designBy |
OpenBSD project
ⓘ
linked to:
OpenBSD
|
| enforcedBy |
MMU (Memory Management Unit)
ⓘ
linked to:
I/O Memory Management Unit
operating system kernel ⓘ page table permission bits ⓘ |
| fullName | Write XOR Execute ⓘ |
| hasGoal |
mitigate buffer overflow attacks
ⓘ
mitigate code injection attacks ⓘ mitigate memory corruption exploits ⓘ mitigate return-to-libc style attacks ⓘ reduce arbitrary code execution risk ⓘ |
| hasProperty |
enforces non-overlap of writable and executable memory permissions
ⓘ
prevents memory pages from being both writable and executable simultaneously ⓘ |
| implementedIn |
kernel memory management code
ⓘ
user-space memory allocators and loaders ⓘ |
| implies |
JIT engines must separate code generation and execution phases
ⓘ
self-modifying code must use special mechanisms ⓘ |
| influenced |
adoption of non-executable memory policies in other operating systems
ⓘ
design of modern executable space protections ⓘ |
| introducedBy | OpenBSD ⓘ |
| introducedInVersion |
OpenBSD 3.3
ⓘ
linked to:
OpenBSD
|
| introducedInYear | 2003 ⓘ |
| relatedTo |
ASLR
ⓘ
DEP (Data Execution Prevention) ⓘ
linked to:
XD bit (Execute Disable Bit)
NX bit ⓘ executable space protection ⓘ stack canaries ⓘ |
| requires |
hardware support for page-level execute permissions
ⓘ
operating system support in the virtual memory subsystem ⓘ |
| securityBenefit |
forces attackers to rely on code reuse techniques
ⓘ
limits ability of attackers to execute injected payloads ⓘ |
| securityLimitation |
does not fix underlying software vulnerabilities
ⓘ
does not prevent all return-oriented programming attacks ⓘ |
| typicalConfiguration |
mark code pages executable and non-writable
ⓘ
mark data pages writable and non-executable ⓘ |
| usedIn | OpenBSD ⓘ |
| usesModel | write-or-execute but not both ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: W^X Description of subject: W^X is a memory protection security mechanism that enforces pages to be either writable or executable, but not both, to mitigate exploits such as buffer overflows.
Referenced by (2)
Full triples — surface form annotated when it differs from this entity's canonical label.