{"id":"CVE-2026-98621","published":"2026-10-18T16:17:14.997","lastModified":"2026-10-19T10:19:26.217","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: gue: reject invalid REMCSUM offsets\n\nThe REMCSUM option carries an absolute checksum start and checksum field\noffset. gue_remcsum() passes them to skb_remcsum_process(), whose\npartial path stores offset - start in the u16 skb->csum_offset variable.\nIf offset is less than start, this underflows.\n\nA forwarded packet can retain CHECKSUM_PARTIAL and reach a NETIF_F_HW_CSUM\ndriver which trusts the metadata, leading skb_copy_and_csum_dev() to write\ntwo bytes about 64 KiB beyond the destination buffer.\n\nReject reversed tuples in validate_gue_flags(), after the existing length\nvalidation, so all GUE parsers enforce the ordering in one place.","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/1d664be4ca49d1696e85239236f4988dfc4653c3","tags":[]},{"url":"https://git.kernel.org/stable/c/1eeec0c51fd5598da44080ed96bbd9880021c28b","tags":[]},{"url":"https://git.kernel.org/stable/c/2566866fc30965d915d0b52b5c3323b362619f0e","tags":[]},{"url":"https://git.kernel.org/stable/c/40aeafbcbc7bc4018e8f74bbbb4d29ed8846f57f","tags":[]},{"url":"https://git.kernel.org/stable/c/43efb1f997e976f386aa89716f55870cd2cff9ad","tags":[]},{"url":"https://git.kernel.org/stable/c/4b9bc21b2396c396d88dd909caaf73d5be6ff593","tags":[]},{"url":"https://git.kernel.org/stable/c/97f907203321eee2cc9132d5c9eb47698fb41d35","tags":[]},{"url":"https://git.kernel.org/stable/c/c20f755338ca234e523dfc943719f194dfc1f903","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}