Описание
In the Linux kernel, the following vulnerability has been resolved:
tunnels: load network headers after skb_cow() in iptunnel_pmtud_build_icmpv6
Sashiko found that iptunnel_pmtud_build_icmp() and
iptunnel_pmtud_build_icmpv6() were caching ip_hdr() and ipv6_hdr()
before an skb_cow() call which can reallocate skb->head.
Fix this possible UAF by initializing the local variables
after the skb_cow() call.
Remove skb_reset_network_header() calls which were not needed.
A flaw was found in the Linux kernel's tunnels module. This vulnerability, categorized as a Use-After-Free (UAF), arises from improper handling of network header pointers during certain packet processing operations. Specifically, functions responsible for building Internet Control Message Protocol (ICMP) packets for Path MTU Discovery (PMTUD) cache header information before memory reallocations, which can lead to the use of freed memory. A local attacker could potentially leverage this to cause a system crash, resulting in a denial of service.
Меры по смягчению последствий
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
Затронутые пакеты
| Платформа | Пакет | Состояние | Рекомендация | Релиз |
|---|---|---|---|---|
| Red Hat Enterprise Linux 10 | kernel | Affected | ||
| Red Hat Enterprise Linux 6 | kernel | Under investigation | ||
| Red Hat Enterprise Linux 7 | kernel | Not affected | ||
| Red Hat Enterprise Linux 7 | kernel-rt | Not affected | ||
| Red Hat Enterprise Linux 9 | kernel-rt | Affected | ||
| Red Hat Enterprise Linux 8 | kernel-rt | Fixed | RHSA-2026:75746 | 05.10.2026 |
| Red Hat Enterprise Linux 8 | kernel | Fixed | RHSA-2026:75747 | 05.10.2026 |
| Red Hat Enterprise Linux 9 | kernel | Fixed | RHSA-2026:76739 | 08.10.2026 |
| Red Hat Enterprise Linux 9 | kernel | Fixed | RHSA-2026:76739 | 08.10.2026 |
Показывать по
Дополнительная информация
Статус:
EPSS
7 High
CVSS3
Связанные уязвимости
In the Linux kernel, the following vulnerability has been resolved: tunnels: load network headers after skb_cow() in iptunnel_pmtud_build_icmp[v6]() Sashiko found that iptunnel_pmtud_build_icmp() and iptunnel_pmtud_build_icmpv6() were caching ip_hdr() and ipv6_hdr() before an skb_cow() call which can reallocate skb->head. Fix this possible UAF by initializing the local variables after the skb_cow() call. Remove skb_reset_network_header() calls which were not needed.
In the Linux kernel, the following vulnerability has been resolved: tunnels: load network headers after skb_cow() in iptunnel_pmtud_build_icmp[v6]() Sashiko found that iptunnel_pmtud_build_icmp() and iptunnel_pmtud_build_icmpv6() were caching ip_hdr() and ipv6_hdr() before an skb_cow() call which can reallocate skb->head. Fix this possible UAF by initializing the local variables after the skb_cow() call. Remove skb_reset_network_header() calls which were not needed.
In the Linux kernel, the following vulnerability has been resolved: t ...
EPSS
7 High
CVSS3