CVE-2026-63920
Linux Linux 취약점
In the Linux kernel, the following vulnerability has been resolved: ipv6: validate extension header length before copying to cmsg ip6_datagram_recv_specific_ctl() builds IPV6_{HOPOPTS,DSTOPTS,RTHDR} cmsgs (and their IPV6_2292* legacy counterparts) by trusting the on-wire hdrlen byte (ptr[1]) when computing the put_cmsg() length. The length was validated only at parse time (ipv6_parse_hopopts(), etc.). An nftables payload-write expression can rewrite hdrlen after parsing and before the skb reaches recvmsg; the write itself is in-bounds but put_cmsg() then reads up to ((hdrlen+1) << 3) = 2040...
- 대응 우선순위
- 점검
- CVSS
- 7.1
- EPSS
- - 백분위 -
- CISA KEV
- 미등록
- 조치 기한
- -
- 공개일
- 2026.07.20