[3.11] gh-144833: Fix use-after-free in SSL module when SSL_new() fails (GH-144843)#144861
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miss-islington wants to merge 1 commit intopython:3.11from
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[3.11] gh-144833: Fix use-after-free in SSL module when SSL_new() fails (GH-144843)#144861miss-islington wants to merge 1 commit intopython:3.11from
miss-islington wants to merge 1 commit intopython:3.11from
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pythonGH-144843) In newPySSLSocket(), when SSL_new() returns NULL, Py_DECREF(self) was called before _setSSLError(get_state_ctx(self), ...), causing a use-after-free. Additionally, get_state_ctx() was called with self (PySSLSocket*) instead of sslctx (PySSLContext*), which is a type confusion bug. Fix by calling _setSSLError() before Py_DECREF() and using sslctx instead of self for get_state_ctx(). (cherry picked from commit c91638c) Co-authored-by: Ramin Farajpour Cami <ramin.blackhat@gmail.com>
This was referenced Feb 16, 2026
caje731
reviewed
Feb 17, 2026
| self->ssl = SSL_new(ctx); | ||
| PySSL_END_ALLOW_THREADS | ||
| if (self->ssl == NULL) { | ||
| _setSSLError(get_state_ctx(sslctx), NULL, 0, __FILE__, __LINE__); |
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For my curiosity - any benefits to moving decref further down? The only thing I can think of is if get_state_ctx begins holding (indirect / chain) references to self again through its argument, moving the decref down is appropriately defensive.
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In newPySSLSocket(), when SSL_new() returns NULL, Py_DECREF(self)
was called before _setSSLError(get_state_ctx(self), ...), causing
a use-after-free. Additionally, get_state_ctx() was called with
self (PySSLSocket*) instead of sslctx (PySSLContext*), which is
a type confusion bug.
Fix by calling _setSSLError() before Py_DECREF() and using
sslctx instead of self for get_state_ctx().
(cherry picked from commit c91638c)
Co-authored-by: Ramin Farajpour Cami ramin.blackhat@gmail.com
newPySSLSocket()whenSSL_new()fails #144833