Common Weakness Enumeration
CWE-1176
Allowed-with-ReviewInefficient CPU Computation
Abstraction: Class · Status: Incomplete
The product performs CPU computations using algorithms that are not as efficient as they could be for the needs of the developer, i.e., the computations can be optimized further.
2 vulnerabilities reference this CWE, most recent first.
CVE-2026-18503 (GCVE-0-2026-18503)
Vulnerability from cvelistv5 – Published: 2026-08-10 13:45 – Updated: 2026-11-10 12:40
VLAI
EPSS
VEX
Title
Super-linear CPU usage for unbounded input to csv.Sniffer.sniff()
Summary
Attacker-controlled CSV samples can trigger super-linear
regular-expression work during dialect sniffing and consume significant
CPU when applications pass unbounded input to csv.Sniffer.sniff().
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-10 17:56 UTC
CWE
Assigner
PSF
CNA
References
10 references
Impacted products
6 products
| Vendor | Product | Version | |
|---|---|---|---|
| Python Software Foundation | CPython |
Affected:
0 , < 3.10.21
(python)
Affected: 3.11.0 , < 3.11.16 (python) Affected: 3.12.0 , < 3.12.14 (python) Affected: 3.13.0 , < 3.13.15 (python) Affected: 3.14.0 , < 3.14.7 (python) Affected: 3.15.0a1 , < 3.15.0rc1 (python) Affected: 3.16.0a1 , < 3.16.0 (python) |
|
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) |
Affected:
V3.1.7 , < *
(custom)
|
|
| Siemens | SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) |
Affected:
V3.1.7 , < *
(custom)
|
|
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) |
Affected:
V3.1.7 , < *
(custom)
|
|
| Siemens | SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AC0) |
Affected:
V3.1.7 , < *
(custom)
|
|
| Siemens | SIPLUS S7-1500 CPU 1518-4 PN/DP MFP (6AG1518-4AX00-4AC0) |
Affected:
V3.1.7 , < *
(custom)
|
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CVE-2024-23323 (GCVE-0-2024-23323)
Vulnerability from cvelistv5 – Published: 2024-02-09 22:50 – Updated: 2024-08-01 22:59
VLAI
EPSS
VEX
Title
Excessive CPU usage when URI template matcher is configured using regex in Envoy
Summary
Envoy is a high-performance edge/middle/service proxy. The regex expression is compiled for every request and can result in high CPU usage and increased request latency when multiple routes are configured with such matchers. This issue has been addressed in released 1.29.1, 1.28.1, 1.27.3, and 1.26.7. Users are advised to upgrade. There are no known workarounds for this vulnerability.
Severity
4.3 (Medium)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-02-12 16:42 UTC
Assigner
GitHub_M
CNA
References
2 references
| URL | Tags |
|---|---|
| https://github.com/envoyproxy/envoy/security/advi… | x_refsource_CONFIRM |
| https://github.com/envoyproxy/envoy/commit/71eeee… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| envoyproxy | envoy |
Affected:
>= 1.29.0, < 1.29.1
Affected: >= 1.28.0, < 1.28.1 Affected: >= 1.27.0, < 1.27.3 Affected: < 1.26.7 |
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No mitigation information available for this CWE.
No CAPEC attack patterns related to this CWE.