名稱: Signal Handler Race Condition
The product uses a signal handler that introduces a race condition.
一般資訊
引入方式
Implementation : Race conditions frequently occur in signal handlers, since signal handlers support asynchronous actions.適用平台
程式語言
名稱： C (Sometimes)名稱： C++ (Sometimes)
常見後果
| 範圍 | 影響 | 可能性 |
|---|---|---|
| Integrity Confidentiality Availability | Modify Application Data, Modify Memory, DoS: Crash, Exit, or Restart, Execute Unauthorized Code or Commands 注意：Attackers may be able to exploit a signal handler race condition to cause the product state to be corrupted. It may be possible to execute arbitrary code by modifying global variables or data structures at unexpected times, violating the assumptions of code that uses this global data. | |
| Access Control | Gain Privileges or Assume Identity 注意：If a signal handler interrupts code that is executing with privileges, it may be possible that the signal handler will also be executed with elevated privileges, possibly making subsequent exploits more severe. |
觀察到的案例
| 參考資料 | 描述 |
|---|---|
CVE-1999-0035 | Signal handler does not disable other signal handlers, allowing it to be interrupted, causing other functionality to access files/etc. with raised privileges |
CVE-2001-0905 | Attacker can send a signal while another signal handler is already running, leading to crash or execution with root privileges |
CVE-2001-1349 | unsafe calls to library functions from signal handler |
CVE-2004-0794 | SIGURG can be used to remotely interrupt signal handler; other variants exist. |
CVE-2004-2259 | SIGCHLD signal to FTP server can cause crash under heavy load while executing non-reentrant functions like malloc/free. |
潛在緩解措施
Phases : RequirementsUse a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Phases : Architecture and Design
Design signal handlers to only set flags, rather than perform complex functionality. These flags can then be checked and acted upon within the main program loop.
Phases : Implementation
Only use reentrant functions within signal handlers. Also, use validation to ensure that state is consistent while performing asynchronous actions that affect the state of execution.
偵測方法
Automated Static Analysis
Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)漏洞對應備注
理由說明 : This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.備註 : Carefully read both the name and description to ensure that this mapping is an appropriate fit. Do not try to 'force' a mapping to a lower-level Base/Variant simply to comply with this preferred level of abstraction.
參考資料
REF-18
The CLASP Application Security ProcessSecure Software, Inc..
https://cwe.mitre.org/documents/sources/TheCLASPApplicationSecurityProcess.pdf
REF-360
Delivering Signals for Fun and ProfitMichal Zalewski.
https://lcamtuf.coredump.cx/signals.txt
REF-361
Race Condition: Signal Handlinghttps://vulncat.fortify.com/en/detail?id=desc.structural.cpp.race_condition_signal_handling#:~:text=Signal%20handling%20race%20conditions%20can,installed%20to%20handle%20multiple%20signals.s
REF-44
24 Deadly Sins of Software SecurityMichael Howard, David LeBlanc, John Viega.
REF-62
The Art of Software Security AssessmentMark Dowd, John McDonald, Justin Schuh.
提交
| 名稱 | 機構 | 日期 | 發布日期 | Version |
|---|---|---|---|---|
| PLOVER | Draft 3 |
修改記錄
| 名稱 | 機構 | 日期 | 備註 |
|---|---|---|---|
| Eric Dalci | Cigital | updated Time_of_Introduction | |
| CWE Content Team | MITRE | updated Applicable_Platforms, Common_Consequences, Relationships, Other_Notes, Taxonomy_Mappings | |
| CWE Content Team | MITRE | updated Observed_Examples, References | |
| CWE Content Team | MITRE | updated Common_Consequences, Demonstrative_Examples, Description, Observed_Examples, Other_Notes, Potential_Mitigations, Relationships | |
| CWE Content Team | MITRE | updated Common_Consequences | |
| CWE Content Team | MITRE | updated Demonstrative_Examples, References, Relationships | |
| CWE Content Team | MITRE | updated Demonstrative_Examples, References | |
| CWE Content Team | MITRE | updated Relationships, Taxonomy_Mappings | |
| CWE Content Team | MITRE | updated Observed_Examples, Relationships | |
| CWE Content Team | MITRE | updated References, Relationships | |
| CWE Content Team | MITRE | updated Potential_Mitigations | |
| CWE Content Team | MITRE | updated Relationships, Research_Gaps | |
| CWE Content Team | MITRE | updated Description | |
| CWE Content Team | MITRE | updated References, Relationships, Time_of_Introduction | |
| CWE Content Team | MITRE | updated Mapping_Notes | |
| CWE Content Team | MITRE | updated Detection_Factors, Weakness_Ordinalities | |
| CWE Content Team | MITRE | updated Common_Consequences, Description, Modes_of_Introduction |
