An algorithmic complexity flaw exists in libsoup's HTTP Range header processing that persists after the CVE-2025-32907 fix. CVE-2025-32907 addressed memory amplification when a client repeated the same range many times in a single Range header. Commit 9bb92f7a corrected merge correctness in soupmessageheadersgetrangesinternal() in libsoup/soup-message-headers.c, but the coalescing loop still removes merged ranges using garrayremoveindex() for each coalesced element. Because GArray is contiguous, each mid-array removal performs an O(N) memmove. When many identical satisfiable ranges are supplied (for example bytes=0-0 repeated thousands of times), the loop performs O(N²) work coalescing them into a single range. The vulnerable path is reachable server-side from handlepartialget() in libsoup/server/http1/soup-server-message-io-http1.c when a SoupServer handler returns HTTP 200 with a non-empty body. No authentication is required. The number of ranges is bounded only by the maximum request header size (~100 KiB), allowing roughly 25,000 ranges per request. Reporter measurements on libsoup HEAD containing the CVE-2025-32907 fix show ~90 ms single-core CPU per such request at the wire maximum, blocking the server's event loop for that duration. This is a CPU exhaustion / availability issue only. No memory corruption or information disclosure occurs. Affected: libsoup versions containing the CVE-2025-32907 fix but not merge request !550. Fixed upstream: MR !550 merged 2026-08-20, replacing per-element removal with O(N) in-place compaction and rejecting Range headers requesting more than 200 ranges. Upstream report: https://gitlab.gnome.org/GNOME/libsoup/-/issues/538 Related: CVE-2025-32907
{
"binaries": [
{
"binary_version": "2.74.2-3ubuntu0.7",
"binary_name": "gir1.2-soup-2.4"
},
{
"binary_version": "2.74.2-3ubuntu0.7",
"binary_name": "libsoup-gnome2.4-1"
},
{
"binary_version": "2.74.2-3ubuntu0.7",
"binary_name": "libsoup2.4-1"
},
{
"binary_version": "2.74.2-3ubuntu0.7",
"binary_name": "libsoup2.4-common"
},
{
"binary_version": "2.74.2-3ubuntu0.7",
"binary_name": "libsoup2.4-tests"
}
]
}{
"binaries": [
{
"binary_version": "2.74.3-6ubuntu1.7",
"binary_name": "gir1.2-soup-2.4"
},
{
"binary_version": "2.74.3-6ubuntu1.7",
"binary_name": "libsoup-2.4-1"
},
{
"binary_version": "2.74.3-6ubuntu1.7",
"binary_name": "libsoup-gnome-2.4-1"
},
{
"binary_version": "2.74.3-6ubuntu1.7",
"binary_name": "libsoup2.4-common"
},
{
"binary_version": "2.74.3-6ubuntu1.7",
"binary_name": "libsoup2.4-tests"
}
]
}{
"binaries": [
{
"binary_version": "3.4.4-5ubuntu0.7",
"binary_name": "gir1.2-soup-3.0"
},
{
"binary_version": "3.4.4-5ubuntu0.7",
"binary_name": "libsoup-3.0-0"
},
{
"binary_version": "3.4.4-5ubuntu0.7",
"binary_name": "libsoup-3.0-common"
},
{
"binary_version": "3.4.4-5ubuntu0.7",
"binary_name": "libsoup-3.0-tests"
}
]
}{
"binaries": [
{
"binary_version": "3.6.6-1",
"binary_name": "gir1.2-soup-3.0"
},
{
"binary_version": "3.6.6-1",
"binary_name": "libsoup-3.0-0"
},
{
"binary_version": "3.6.6-1",
"binary_name": "libsoup-3.0-common"
},
{
"binary_version": "3.6.6-1",
"binary_name": "libsoup-3.0-tests"
}
]
}{
"binaries": [
{
"binary_version": "2.70.0-1ubuntu0.5+esm2",
"binary_name": "gir1.2-soup-2.4"
},
{
"binary_version": "2.70.0-1ubuntu0.5+esm2",
"binary_name": "libsoup-gnome2.4-1"
},
{
"binary_version": "2.70.0-1ubuntu0.5+esm2",
"binary_name": "libsoup2.4-1"
},
{
"binary_version": "2.70.0-1ubuntu0.5+esm2",
"binary_name": "libsoup2.4-tests"
}
]
}{
"binaries": [
{
"binary_version": "3.0.7-0ubuntu1+esm7",
"binary_name": "gir1.2-soup-3.0"
},
{
"binary_version": "3.0.7-0ubuntu1+esm7",
"binary_name": "libsoup-3.0-0"
},
{
"binary_version": "3.0.7-0ubuntu1+esm7",
"binary_name": "libsoup-3.0-common"
},
{
"binary_version": "3.0.7-0ubuntu1+esm7",
"binary_name": "libsoup-3.0-tests"
}
]
}{
"binaries": [
{
"binary_version": "2.74.3-10.1ubuntu5+esm1",
"binary_name": "gir1.2-soup-2.4"
},
{
"binary_version": "2.74.3-10.1ubuntu5+esm1",
"binary_name": "libsoup-2.4-1"
},
{
"binary_version": "2.74.3-10.1ubuntu5+esm1",
"binary_name": "libsoup-gnome-2.4-1"
},
{
"binary_version": "2.74.3-10.1ubuntu5+esm1",
"binary_name": "libsoup2.4-common"
},
{
"binary_version": "2.74.3-10.1ubuntu5+esm1",
"binary_name": "libsoup2.4-tests"
}
]
}