Run static analysis (SAST) on the codebase looking for the unsafe pattern in the data flow.
CWE-1261 Base Draft
Improper Handling of Single Event Upsets
This vulnerability occurs when hardware logic fails to properly manage single-event upsets (SEUs), which are temporary bit flips caused by environmental factors.
Definition
What is CWE-1261?
This vulnerability occurs when hardware logic fails to properly manage single-event upsets (SEUs), which are temporary bit flips caused by environmental factors.
Modern hardware is becoming more vulnerable to temporary errors called single-event upsets (SEUs). These random bit flips are caused by internal factors like electrical interference or external sources like cosmic radiation. Unlike permanent hardware faults, SEUs are transient but can have serious security consequences if they affect critical system components.
When an SEU occurs in a security-sensitive module—such as a privilege manager or cryptographic engine—it can bypass critical protections. For example, a single bit flip might incorrectly elevate a user's privileges or corrupt cryptographic keys. Developers must design hardware logic with detection and correction mechanisms, like parity checks or error-correcting code (ECC) memory, to prevent these temporary failures from compromising system security.
Real-world impact
Real-world CVEs caused by CWE-1261
No public CVE references are linked to this CWE in MITRE's catalog yet.
How attackers exploit it
Step-by-step attacker path
- 1
This is an example from [REF-1089]. See the reference for full details of this issue.
- 2
Parity is error detecting but not error correcting.
- 3
In 2016, a security researcher, who was also a patient using a pacemaker, was on an airplane when a bit flip occurred in the pacemaker, likely due to the higher prevalence of cosmic radiation at such heights. The pacemaker was designed to account for bit flips and went into a default safe mode, which still forced the patient to go to a hospital to get it reset. The bit flip also inadvertently enabled the researcher to access the crash file, perform reverse engineering, and detect a hard-coded key. [REF-1101]
Vulnerable code example
Vulnerable Other
Parity is error detecting but not error correcting.
Due to single-event upsets, bits are flipped in memories. As a result, memory-parity checks fail, which results in restart and a temporary denial of service of two to three minutes. Secure code example
Secure Other
Using error-correcting codes could have avoided the restart caused by SEUs. What changed: the unsafe sink is replaced (or the input is validated/escaped) so the same payload no longer triggers the weakness.
Prevention checklist
How to prevent CWE-1261
- Architecture and Design Implement triple-modular redundancy around security-sensitive modules.
- Architecture and Design SEUs mostly affect SRAMs. For SRAMs storing security-critical data, implement Error-Correcting-Codes (ECC) and Address Interleaving.
Detection signals
How to detect CWE-1261
Run dynamic application security testing against the live endpoint.
Watch runtime logs for unusual exception traces, malformed input, or authorization bypass attempts.
Code review: flag any new code that handles input from this surface without using the validated framework helpers.
CWE-1261
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Frequently asked questions What is CWE-1261?
How serious is CWE-1261?
What languages or platforms are affected by CWE-1261?
How can I prevent CWE-1261?
How does Plexicus detect and fix CWE-1261?
Where can I learn more about CWE-1261?
Frequently asked questions
What is CWE-1261?
This vulnerability occurs when hardware logic fails to properly manage single-event upsets (SEUs), which are temporary bit flips caused by environmental factors.
How serious is CWE-1261?
MITRE has not published a likelihood-of-exploit rating for this weakness. Treat it as medium-impact until your threat model proves otherwise.
What languages or platforms are affected by CWE-1261?
MITRE lists the following affected platforms: Not OS-Specific, Not Architecture-Specific, Not Technology-Specific.
How can I prevent CWE-1261?
Implement triple-modular redundancy around security-sensitive modules. SEUs mostly affect SRAMs. For SRAMs storing security-critical data, implement Error-Correcting-Codes (ECC) and Address Interleaving.
How does Plexicus detect and fix CWE-1261?
Plexicus's SAST engine matches the data-flow signature for CWE-1261 on every commit. When a match is found, our Codex Remedium agent opens a fix PR with the corrected code, tests, and a one-line summary for the reviewer.
Where can I learn more about CWE-1261?
MITRE publishes the canonical definition at https://cwe.mitre.org/data/definitions/1261.html. You can also reference OWASP and NIST documentation for adjacent guidance.
Related weaknesses
Weaknesses related to CWE-1261
CWE-1384 Parent
Improper Handling of Physical or Environmental Conditions
This weakness occurs when a hardware device fails to manage unexpected physical or environmental situations, whether they happen naturally…
CWE-1247 Sibling
Improper Protection Against Voltage and Clock Glitches
This vulnerability occurs when a hardware device lacks proper physical safeguards against deliberate electrical manipulation. Without…
CWE-1332 Sibling
Improper Handling of Faults that Lead to Instruction Skips
This vulnerability occurs when a hardware device lacks or incorrectly implements the necessary circuitry or sensors to detect and respond…
CWE-1351 Sibling
Improper Handling of Hardware Behavior in Exceptionally Cold Environments
This weakness occurs when a hardware device or its firmware lacks proper safeguards to maintain security functions when operated in…
CWE-1254 Peer
Incorrect Comparison Logic Granularity
This vulnerability occurs when a system compares sensitive data, like passwords or authentication tokens, piece-by-piece instead of as a…
Resources
Further reading
- MITRE — official CWE-1261 https://cwe.mitre.org/data/definitions/1261.html
- Single Event Upset: An Embedded Tutorial https://www.eng.auburn.edu/~agrawvd/TALKS/tutorial_6pg.pdf
- Single Event Upsets in Implantable Cardioverter Defibrillators https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=736549&tag=1
- Single Event Effects in FPGA Devices 2015-2016 https://ntrs.nasa.gov/search.jsp?R=20160007754
- Cisco 12000 Single Event Upset Failures Overview and Work Around Summary https://www.cisco.com/c/en/us/support/docs/field-notices/200/fn25994.html
- Different Ways to Mitigate Soft Errors in Asynchronous SRAMs - KBA90939 https://community.infineon.com/t5/Knowledge-Base-Articles/Different-Ways-to-Mitigate-Soft-Errors-in-Asynchronous-SRAMs-KBA90939/ta-p/257944
- Cosmic particles can change elections and cause plans to fall through the sky, scientists warn https://www.independent.co.uk/news/science/subatomic-particles-cosmic-rays-computers-change-elections-planes-autopilot-a7584616.html
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