Note: This bug is displayed in read-only format because the product is no longer active in Red Hat Bugzilla.

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Stand-alone reproducer:

wget https://raw.githubusercontent.com/redhat-qe-security/certgen/master/certgen/lib.sh
. lib.sh
x509KeyGen ca 
x509SelfSign ca
x509KeyGen server
x509CertSign --CA ca server

openssl s_server -key server/key.pem -cert server/cert.pem -www -tls1_2 -cipher ECDHE-RSA-AES128-SHA256

# in another terminal:
git clone https://github.com/tomato42/tlsfuzzer
pushd tlsfuzzer
git clone https://github.com/tlsfuzzer/tlslite-ng .tlslite-ng
ln -s .tlslite-ng/tlslite tlslite
git clone https://github.com/tlsfuzzer/python-ecdsa .python-ecdsa
ln -s .python-ecdsa/src/ecdsa ecdsa
PYTHONPATH=. python3 scripts/test-fuzzed-plaintext.py -h localhost -p 4433 -C TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256 sanity

The issue affects all AES128-SHA256 ciphersuites, but it requires a different kind of reproducer (see the upstream issue tracker).