Client crash or heap disclosure via underflow
Published Jul 24, 2026 · Updated Jul 24, 2026
Out-of-bounds read in libsoup on Red Hat Enterprise Linux 6 through 10 allows remote attackers to crash clients via crafted multipart responses. soup_filter_input_stream_read_until() subtracts multipart boundary lengths without preventing unsigned underflow, causing a heap buffer over-read. Exploitation requires a client to parse a response from an attacker-controlled HTTP server; the over-read crashes the client or exposes adjacent heap data.
Summary
What happened
Out-of-bounds read in libsoup on Red Hat Enterprise Linux 6 through 10 allows remote attackers to crash clients via crafted multipart responses. soup_filter_input_stream_read_until() subtracts multipart boundary lengths without preventing unsigned underflow, causing a heap buffer over-read. Exploitation requires a client to parse a response from an attacker-controlled HTTP server; the over-read crashes the client or exposes adjacent heap data.
The record
- CVE
- CVE-2026-66337
- Published
- Jul 24, 2026
- Updated
- Jul 24, 2026
- Vendor
- 389 Directory Server
- Product
- Red Hat Enterprise Linux 6
- Classifications
- CWE-125
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 24, 2026CVE publishedPublication date reported by the CVE source.
- Jul 24, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
Public exploit references
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Technologies
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Your stack
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