Host-memory disclosure via unchecked UDPv6 length
Published Jun 15, 2021 · Updated Aug 3, 2024
Out-of-bounds read in libslirp before 4.6.0 allows guest OS users to obtain indirect disclosure of host memory via a short UDPv6 packet. In udp6_input(), a packet shorter than struct udphdr is cast to that structure without first verifying the remaining mbuf length, so reads extend beyond the working buffer. A user must control networking from a guest using SLiRP; the flaw exposes adjacent host memory to that guest without modifying host data or interrupting service.
Summary
What happened
Out-of-bounds read in libslirp before 4.6.0 allows guest OS users to obtain indirect disclosure of host memory via a short UDPv6 packet. In udp6_input(), a packet shorter than struct udphdr is cast to that structure without first verifying the remaining mbuf length, so reads extend beyond the working buffer. A user must control networking from a guest using SLiRP; the flaw exposes adjacent host memory to that guest without modifying host data or interrupting service.
The record
- CVE
- CVE-2021-3593
- Published
- Jun 15, 2021
- Updated
- Aug 3, 2024
- Vendor
- Libslirp Project
- Product
- libslirp
- Classifications
- CWE-824
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jun 15, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record 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=libslirp 4.6.0
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
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