transfer: clear the URL pointer in OOM to avoid UAF#21123
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transfer: clear the URL pointer in OOM to avoid UAF#21123
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Since the pointer can be extracted with CURLINFO_EFFECTIVE_URL later it must not linger pointing to freed memory. Founde by Codex Security
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Analysis of PR #21123 at 2343f58f: Test 1350 failed, which has NOT been flaky recently, so there could be a real issue in this PR. Note that this test has failed in 2 different CI jobs (the link just goes to one of them). Generated by Testclutch |
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Pull request overview
Fixes a potential use-after-free where data->state.url could continue to reference a freed URL string if curl_url_get() fails while CURLOPT_CURLU is in use, making later CURLINFO_EFFECTIVE_URL queries unsafe.
Changes:
- Clear
data->state.urlwhencurl_url_get(..., CURLUPART_URL, ...)fails inCurl_pretransfer()to avoid dangling pointers.
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dkarpov1970
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Apr 7, 2026
Since the pointer can be extracted with CURLINFO_EFFECTIVE_URL later it must not linger pointing to freed memory. Found by Codex Security Closes curl#21123
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Since the pointer can be extracted with CURLINFO_EFFECTIVE_URL later it must not linger pointing to freed memory.
Founde by Codex Security