CVE-2021-29508
CVSS v3
9.1
CRITICAL
EPSS Score
1.6 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
Due to how Wire handles type information in its serialization format, malicious payloads can be passed to a deserializer. e.g. using a surrogate on the sender end, an attacker can pass information about a different type for the receiving end. And by doing so allowing the serializer to create any type on the deserializing end. This is the same issue that exists for .NET BinaryFormatter https://docs.microsoft.com/en-us/visualstudio/code-quality/ca2300?view=vs-2019. This also applies to the fork of Wire.
Technical details
- Published
- 2021-05-11
Frequently asked questions
What is CVE-2021-29508?
Due to how Wire handles type information in its serialization format, malicious payloads can be passed to a deserializer. e.g. using a surrogate on the sender end, an attacker can pass information about a different type for the receiving end. And by doing so allowing the serializer to create any type on the deserializing end. This is the same issue that exists for .NET BinaryFormatter https://docs.microsoft.com/en-us/visualstudio/code-quality/ca2300?view=vs-2019. This also applies to the fork of Wire.
Is CVE-2021-29508 actively exploited?
Active exploitation of CVE-2021-29508 has not been confirmed. Its EPSS score was 1.6% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-29508?
CVE-2021-29508 has a CVSS v3 base score of 9.1 (CRITICAL severity).
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