CVE-2026-69249: CWE-400: Uncontrolled Resource Consumption in pyca cryptography
A resource exhaustion vulnerability exists in the python-cryptography package prior to version 49.0.0. When processing invalid certificate chains containing duplicate self-signed certificates, the recursive validation function can be triggered to perform excessive work, causing delays exceeding 5 seconds. This issue does not affect the correctness of validation or system integrity but can degrade availability through denial of service. The vulnerability is fixed in version 49.0.0.
AI Analysis
Technical Summary
CVE-2026-69249 is an uncontrolled resource consumption vulnerability (CWE-400) in the pyca cryptography package before version 49.0.0. The recursive function build_chain_inner, used for certificate chain validation, does not de-duplicate previously analyzed candidates when resolving invalid chains with duplicate self-signed certificates. This leads to exponential processing time growth, allowing an attacker-controlled certificate chain to cause significant delays. Although the recursion is bounded by a maximum chain depth, the amplification can cause processing to exceed 5 seconds, enabling a denial of service attack. The issue does not compromise validation correctness or system integrity. The vulnerability is resolved in version 49.0.0.
Potential Impact
An attacker can supply a crafted certificate chain with duplicate self-signed certificates that triggers excessive recursive processing in the certificate validation logic. This results in high CPU usage and delays in processing, potentially causing denial of service by exhausting resources. There is no impact on data integrity or confidentiality, only availability is affected.
Mitigation Recommendations
This vulnerability is fixed in python-cryptography version 49.0.0. Users should upgrade to version 49.0.0 or later to remediate this issue. No other mitigations are indicated.
CVE-2026-69249: CWE-400: Uncontrolled Resource Consumption in pyca cryptography
Description
A resource exhaustion vulnerability exists in the python-cryptography package prior to version 49.0.0. When processing invalid certificate chains containing duplicate self-signed certificates, the recursive validation function can be triggered to perform excessive work, causing delays exceeding 5 seconds. This issue does not affect the correctness of validation or system integrity but can degrade availability through denial of service. The vulnerability is fixed in version 49.0.0.
CVSS v4.0
Score 8.7high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-69249 is an uncontrolled resource consumption vulnerability (CWE-400) in the pyca cryptography package before version 49.0.0. The recursive function build_chain_inner, used for certificate chain validation, does not de-duplicate previously analyzed candidates when resolving invalid chains with duplicate self-signed certificates. This leads to exponential processing time growth, allowing an attacker-controlled certificate chain to cause significant delays. Although the recursion is bounded by a maximum chain depth, the amplification can cause processing to exceed 5 seconds, enabling a denial of service attack. The issue does not compromise validation correctness or system integrity. The vulnerability is resolved in version 49.0.0.
Potential Impact
An attacker can supply a crafted certificate chain with duplicate self-signed certificates that triggers excessive recursive processing in the certificate validation logic. This results in high CPU usage and delays in processing, potentially causing denial of service by exhausting resources. There is no impact on data integrity or confidentiality, only availability is affected.
Mitigation Recommendations
This vulnerability is fixed in python-cryptography version 49.0.0. Users should upgrade to version 49.0.0 or later to remediate this issue. No other mitigations are indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-08-03T19:54:19.852Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a710cc4bf32cb7a3449087d
Added to database: 08/03/2026, 21:48:52 UTC
Last enriched: 08/03/2026, 22:02:52 UTC
Last updated: 08/03/2026, 22:02:52 UTC
Views: 3
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