Fix off-by-one s_client overflows#30731
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There are one byte buffer overflows possible in s_client's handling of STARTTLS in various protocols. If a server's response fills the entire buffer (16k) then we attempt to add a NUL terminator one byte off the end of the buffer. This was reported by Igor Morgenstern from AISLE to openssl-security and assessed by the security team as "bug or hardening only".
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See also the backport in #30732 |
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There are one byte buffer overflows possible in s_client's handling of STARTTLS in various protocols. If a server's response fills the entire buffer (16k) then we attempt to add a NUL terminator one byte off the end of the buffer. This was reported by Igor Morgenstern from AISLE to openssl-security and assessed by the security team as "bug or hardening only". Reviewed-by: Paul Dale <paul.dale@oracle.com> Reviewed-by: Tomas Mraz <tomas@openssl.foundation> Reviewed-by: Eugene Syromiatnikov <esyr@openssl.org> Reviewed-by: Nikola Pajkovsky <nikolap@openssl.org> MergeDate: Sat Apr 11 16:16:24 2026 (Merged from #30731)
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There are one byte buffer overflows possible in s_client's handling of STARTTLS in various protocols. If a server's response fills the entire buffer (16k) then we attempt to add a NUL terminator one byte off the end of the buffer. This was reported by Igor Morgenstern from AISLE to openssl-security and assessed by the security team as "bug or hardening only". Reviewed-by: Paul Dale <paul.dale@oracle.com> Reviewed-by: Tomas Mraz <tomas@openssl.foundation> Reviewed-by: Eugene Syromiatnikov <esyr@openssl.org> Reviewed-by: Nikola Pajkovsky <nikolap@openssl.org> MergeDate: Sat Apr 11 16:25:52 2026 (Merged from #30731)
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There are one byte buffer overflows possible in s_client's handling of STARTTLS in various protocols. If a server's response fills the entire buffer (16k) then we attempt to add a NUL terminator one byte off the end of the buffer.
This was reported by Igor Morgenstern from AISLE to openssl-security and assessed by the security team as "bug or hardening only".