CVE-2019-1559 advisory - what is "non-stiched" ciphersuite means?

[M K Saravanan]

Hi,

In the context of https://www.openssl.org/news/secadv/20190226.txt

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In order for this to be exploitable "non-stitched" ciphersuites must be in use.
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what is "non-stitched" ciphersuites means?

with regards,
Saravanan