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        "dateUpdated": "2026-09-04T16:07:27.046Z"
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            "title": "Libsoup: libsoup: http/2 client crash in on_data_source_read_callback when settings initial_window_size shrinks during deferred body read",
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                        "attackComplexity": "HIGH",
                        "attackVector": "NETWORK",
                        "availabilityImpact": "HIGH",
                        "baseScore": 5.9,
                        "baseSeverity": "MEDIUM",
                        "confidentialityImpact": "NONE",
                        "integrityImpact": "NONE",
                        "privilegesRequired": "NONE",
                        "scope": "UNCHANGED",
                        "userInteraction": "NONE",
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                    "value": "A flaw was found in libsoup. When a client sends an HTTP/2 request body from a non-pollable input stream, the library can buffer more data than the current flow-control window later allows. A malicious HTTP/2 server can shrink SETTINGS_INITIAL_WINDOW_SIZE while that buffered read is still in progress. The client then copies the full buffer into a smaller DATA callback without a runtime bounds check, which can abort the process or fail the HTTP/2 session."
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                    "product": "Red Hat Enterprise Linux 6",
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                    "url": "https://gitlab.gnome.org/GNOME/libsoup/-/blob/master/libsoup/http2/soup-client-message-io-http2.c"
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                {
                    "url": "https://gitlab.gnome.org/GNOME/libsoup/-/work_items/551"
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            ],
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            "workarounds": [
                {
                    "lang": "en",
                    "value": "Do not HTTP/2-upload from non-pollable streams (e.g. GFileInputStream) to untrusted servers. soup_message_set_request_body_from_bytes() is the pollable path. Assertions abort instead of returning an oversized length; that is not a fix."
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            ],
            "timeline": [
                {
                    "lang": "en",
                    "time": "2026-09-03T17:19:37.253Z",
                    "value": "Reported to Red Hat."
                },
                {
                    "lang": "en",
                    "time": "2026-09-03T00:00:00.000Z",
                    "value": "Made public."
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "value": "Red Hat would like to thank xtromera for reporting this issue."
                }
            ],
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