Authenticated memory corruption via unchecked filename concatenation
Published Jun 20, 2025 · Updated Jun 23, 2025
Stack-based buffer overflow in D-Link DIR-825 2.03 allows remote authenticated users to overwrite memory through a crafted HTTP POST request. The do_file handler appends a request-derived filename into a 34-byte stack buffer with strcat without checking the resulting length. Low-privilege access is required; the disclosed proof of concept demonstrates the overwrite but not a specific crash or code-execution outcome.
Summary
What happened
Stack-based buffer overflow in D-Link DIR-825 2.03 allows remote authenticated users to overwrite memory through a crafted HTTP POST request. The do_file handler appends a request-derived filename into a 34-byte stack buffer with strcat without checking the resulting length. Low-privilege access is required; the disclosed proof of concept demonstrates the overwrite but not a specific crash or code-execution outcome.
The record
- CVE
- CVE-2025-6291
- Published
- Jun 20, 2025
- Updated
- Jun 23, 2025
- Vendor
- D-Link
- Product
- DIR-825
- Classifications
- CWE-119, CWE-121, T1190
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jun 20, 2025CVE publishedPublication date reported by the CVE source.
- Jun 23, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=2.03
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- DIR-825 do_file proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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