Denial of service via unbounded PBKDF2 iterations
Published Jun 9, 2026 · Updated Jun 9, 2026
Resource-consumption flaw in Red Hat Directory Server allows remote authenticated users with high privileges to cause a service hang. The Rust pwdchan PBKDF2-SHA256 verification path passes a stored hash iteration count to the PBKDF2 function without enforcing an upper bound. Exploitation requires the ability to modify a user's stored password hash; authenticating as that user then consumes excessive CPU and interrupts directory service availability.
Summary
What happened
Resource-consumption flaw in Red Hat Directory Server allows remote authenticated users with high privileges to cause a service hang. The Rust pwdchan PBKDF2-SHA256 verification path passes a stored hash iteration count to the PBKDF2 function without enforcing an upper bound. Exploitation requires the ability to modify a user's stored password hash; authenticating as that user then consumes excessive CPU and interrupts directory service availability.
The record
- CVE
- CVE-2026-11790
- Published
- Jun 9, 2026
- Updated
- Jun 9, 2026
- Vendor
- 389 Directory Server
- Product
- Red Hat Directory Server
- Classifications
- CWE-400, T1499.004
- Attack vector
- network
- Privileges
- admin
Timeline
How it unfolded
- Jun 9, 2026CVE publishedPublication date reported by the CVE source.
- Jun 9, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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