CVE ID :CVE-2026-43501<\/p>\n
Published : May 21, 2026, 12:17 p.m. | 41\u00a0minutes ago<\/p>\n
Description :In the Linux kernel, the following vulnerability has been resolved:<\/p>\n
ipv6: rpl: reserve mac_len headroom when recompressed SRH grows<\/p>\n
ipv6_rpl_srh_rcv() decompresses an RFC 6554 Source Routing Header, swaps
\nthe next segment into ipv6_hdr->daddr, recompresses, then pulls the old
\nheader and pushes the new one plus the IPv6 header back. The
\nrecompressed header can be larger than the received one when the swap
\nreduces the common-prefix length the segments share with daddr (CmprI=0,
\nCmprE>0, seg[0][0] != daddr[0] gives the maximum +8 bytes).<\/p>\n
pskb_expand_head() was gated on segments_left == 0, so on earlier
\nsegments the push consumed unchecked headroom. Once skb_push() leaves
\nfewer than skb->mac_len bytes in front of data,
\nskb_mac_header_rebuild()’s call to:<\/p>\n
\tskb_set_mac_header(skb, -skb->mac_len);<\/p>\n
will store (data – head) – mac_len into the u16 mac_header field, which
\nwraps to ~65530, and the following memmove() writes mac_len bytes ~64KiB
\npast skb->head.<\/p>\n
A single AF_INET6\/SOCK_RAW\/IPV6_HDRINCL packet over lo with a two
\nsegment type-3 SRH (CmprI=0, CmprE=15) reaches headroom 8 after one
\npass; KASAN reports a 14-byte OOB write in ipv6_rthdr_rcv.<\/p>\n
Fix this by expanding the head whenever the remaining room is less than
\nthe push size plus mac_len, and request that much extra so the rebuilt
\nMAC header fits afterwards.<\/p>\n
Severity: 0.0 | NA<\/p>\n
Visit the link for more details, such as CVSS details, affected products, timeline, and more…\u00a0<\/p>\n","protected":false},"excerpt":{"rendered":"
CVE ID :CVE-2026-43501 Published : May 21, 2026, 12:17 p.m. | 41\u00a0minutes ago Description :In the Linux kernel, the following vulnerability has been resolved: ipv6: rpl: reserve mac_len headroom when recompressed SRH grows ipv6_rpl_srh_rcv() decompresses an RFC 6554 Source Routing Header, swaps the next segment into ipv6_hdr->daddr, recompresses, then pulls the old header and pushes …<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[],"class_list":["post-78689","post","type-post","status-publish","format-standard","hentry","category-vulnerability"],"_links":{"self":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts\/78689","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/comments?post=78689"}],"version-history":[{"count":0,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/posts\/78689\/revisions"}],"wp:attachment":[{"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/media?parent=78689"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/categories?post=78689"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/afaghhosting.net\/blog\/wp-json\/wp\/v2\/tags?post=78689"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}