CWE-911

Podatność use-after-free w podsystemie UMTX jądra FreeBSD pozwala nieuwierzytelnionemu atakującemu na zdalne wykonanie kodu lub ucieczkę z sandboxa Capsicum. Otrzymała maksymalną ocenę CVSS 10.0, co czyni ją podatnością krytyczną wymagającą natychmiastowej reakcji.

Podatność w podsystemie KVM arm64 jądra Linux dotyczy błędu zarządzania referencjami w cache translacji vgic-its, który może prowadzić do zwolnienia pamięci będącej nadal w użyciu (use-after-free). Ze względu na krytyczny wynik CVSS 9.3 i możliwość wpływu na poufność, integralność oraz dostępność systemu, podatność wymaga pilnego załatania.

When the JAIL_AT_DESC flag is specified, kern_jail_set() and kern_jail_get() released the reference to the caller's current prison before looking up the jail descriptor. If the descriptor lookup failed, error-handling paths released the same reference a second time. An unprivileged local user can trigger a prison reference count underflow, which may cause the prison structure to be freed while still in use. When this is done on the jail host, the bug will generally result in an immediate panic. However, if the user is running in a jail, then it may be possible to exploit the bug to elevate privileges.

In the Linux kernel, the following vulnerability has been resolved: net: ipv6: fix NOREF dst use in seg6 and rpl lwtunnels seg6_input_core() and rpl_input() call ip6_route_input() which sets a NOREF dst on the skb, then pass it to dst_cache_set_ip6() invoking dst_hold() unconditionally. On PREEMPT_RT, ksoftirqd is preemptible and a higher-priority task can release the underlying pcpu_rt between the lookup and the caching through a concurrent FIB lookup on a shared nexthop. Simplified race sequence: ksoftirqd/X higher-prio task (same CPU X) ----------- -------------------------------- seg6_input_core(,skb)/rpl_input(skb) dst_cache_get() -> miss ip6_route_input(skb) -> ip6_pol_route(,skb,flags) [RT6_LOOKUP_F_DST_NOREF in flags] -> FIB lookup resolves fib6_nh [nhid=N route] -> rt6_make_pcpu_route() [creates pcpu_rt, refcount=1] pcpu_rt->sernum = fib6_sernum [fib6_sernum=W] -> cmpxchg(fib6_nh.rt6i_pcpu, NULL, pcpu_rt) [slot was empty, store succeeds] -> skb_dst_set_noref(skb, dst) [dst is pcpu_rt, refcount still 1] rt_genid_bump_ipv6() -> bumps fib6_sernum [fib6_sernum from W to Z] ip6_route_output() -> ip6_pol_route() -> FIB lookup resolves fib6_nh [nhid=N] -> rt6_get_pcpu_route() pcpu_rt->sernum != fib6_sernum [W <> Z, stale] -> prev = xchg(rt6i_pcpu, NULL) -> dst_release(prev) [prev is pcpu_rt, refcount 1->0, dead] dst = skb_dst(skb) [dst is the dead pcpu_rt] dst_cache_set_ip6(dst) -> dst_hold() on dead dst -> WARN / use-after-free For the race to occur, ksoftirqd must be preemptible (PREEMPT_RT without PREEMPT_RT_NEEDS_BH_LOCK) and a concurrent task must be able to release the pcpu_rt. Shared nexthop objects provide such a path, as two routes pointing to the same nhid share the same fib6_nh and its rt6i_pcpu entry. Fix seg6_input_core() and rpl_input() by calling skb_dst_force() after ip6_route_input() to force the NOREF dst into a refcounted one before caching. The output path is not affected as ip6_route_output() already returns a refcounted dst.

In the Linux kernel, the following vulnerability has been resolved: net: skbuff: fix missing zerocopy reference in pskb_carve helpers pskb_carve_inside_header() and pskb_carve_inside_nonlinear() both copy the old skb_shared_info header into a new buffer via memcpy(), which includes the destructor_arg pointer (uarg) for MSG_ZEROCOPY skbs. Neither function calls net_zcopy_get() for the new shinfo, creating an unaccounted holder: every skb_shared_info with destructor_arg set will call skb_zcopy_clear() once when freed, but the corresponding net_zcopy_get() was never called for the new copy. Repeated calls drive uarg->refcnt to zero prematurely, freeing ubuf_info_msgzc while TX skbs still hold live destructor_arg pointers. KASAN reports use-after-free on a freed ubuf_info_msgzc: BUG: KASAN: slab-use-after-free in skb_release_data+0x77b/0x810 Read of size 8 at addr ffff88801574d3e8 by task poc/220 Call Trace: skb_release_data+0x77b/0x810 kfree_skb_list_reason+0x13e/0x610 skb_release_data+0x4cd/0x810 sk_skb_reason_drop+0xf3/0x340 skb_queue_purge_reason+0x282/0x440 rds_tcp_inc_free+0x1e/0x30 rds_recvmsg+0x354/0x1780 __sys_recvmsg+0xdf/0x180 Allocated by task 219: msg_zerocopy_realloc+0x157/0x7b0 tcp_sendmsg_locked+0x2892/0x3ba0 Freed by task 219: ip_recv_error+0x74a/0xb10 tcp_recvmsg+0x475/0x530 The skb consuming the late access still referenced the same uarg via shinfo->destructor_arg copied by pskb_carve_inside_nonlinear() without a refcount bump. This has been verified to be reliably exploitable: a working proof-of-concept achieves full root privilege escalation from an unprivileged local user on a default kernel configuration. The fix follows the pattern of pskb_expand_head() which has the same memcpy/cloned structure. For pskb_carve_inside_header(), net_zcopy_get() is placed after skb_orphan_frags() succeeds, so the orphan error path needs no cleanup. For pskb_carve_inside_nonlinear(), net_zcopy_get() is placed after all failure points and just before skb_release_data(), so no error path needs cleanup at all -- matching pskb_expand_head() more closely and avoiding the need for a balancing net_zcopy_put().

Software installed and run as a non-privileged user may conduct improper GPU system calls to trigger use-after-free kernel exceptions.

The reference count changes made as part of the CVE-2023-33951 and CVE-2023-33952 fixes exposed a use-after-free flaw in the way memory objects were handled when they were being used to store a surface. When running inside a VMware guest with 3D acceleration enabled, a local, unprivileged user could potentially use this flaw to escalate their privileges.

Improper Update of Reference Count vulnerability in net/sched of Linux Kernel allows local attacker to cause privilege escalation to root. This issue affects: Linux Kernel versions prior to 5.18; version 4.14 and later versions.

This vulnerability allows remote attackers to create a denial-of-service condition on affected installations of Unified Automation OPC UA C++ Demo Server 1.7.6-537. Authentication is not required to exploit this vulnerability. The specific flaw exists within the OpcUa_SecureListener_ProcessSessionCallRequest method. A crafted OPC UA message can force the server to incorrectly update a reference count. An attacker can leverage this vulnerability to create a denial-of-service condition on the system. Was ZDI-CAN-16927.

An Improper Handling of Unexpected Data Type vulnerability in the handling of SIP calls in Juniper Networks Junos OS on SRX Series and MX Series platforms allows an attacker to cause a memory leak leading to Denial of Services (DoS). This issue occurs on all MX Series platforms with MS-MPC or MS-MIC card and all SRX Series platforms where SIP ALG is enabled. Successful exploitation of this vulnerability prevents additional SIP calls and applications from succeeding. The SIP ALG needs to be enabled, either implicitly / by default or by way of configuration. To confirm whether SIP ALG is enabled on SRX use the following command: user@host> show security alg status | match sip SIP : Enabled This issue affects Juniper Networks Junos OS on SRX Series and on MX Series: All versions prior to 19.3R3-S7; 19.4 versions prior to 19.4R2-S8, 19.4R3-S10; 20.1 versions 20.1R1 and later versions; 20.2 versions prior to 20.2R3-S6; 20.3 versions prior to 20.3R3-S6; 20.4 versions prior to 20.4R3-S5; 21.1 versions prior to 21.1R3-S5; 21.2 versions prior to 21.2R3-S1; 21.3 versions prior to 21.3R3; 21.4 versions prior to 21.4R2-S2, 21.4R3; 22.1 versions prior to 22.1R1-S2, 22.1R2, 22.1R3-S1. This issue does not affect Juniper Networks Junos OS on SRX Series and on MX Series: All versions prior to 18.2R1.

An Improper Update of Reference Count vulnerability in the kernel of Juniper Networks Junos OS Evolved allows an unauthenticated, network-based attacker to trigger a counter overflow, eventually causing a Denial of Service (DoS). This issue affects Juniper Networks Junos OS Evolved: All versions prior to 20.4R3-S1-EVO; 21.1 versions prior to 21.1R3-EVO; 21.2 versions prior to 21.2R3-EVO; 21.3 versions prior to 21.3R2-EVO. This issue does not affect Juniper Networks Junos OS.

In the Linux kernel, the following vulnerability has been resolved: iommu/arm-smmu: Fix arm_smmu_device refcount leak when arm_smmu_rpm_get fails arm_smmu_rpm_get() invokes pm_runtime_get_sync(), which increases the refcount of the "smmu" even though the return value is less than 0. The reference counting issue happens in some error handling paths of arm_smmu_rpm_get() in its caller functions. When arm_smmu_rpm_get() fails, the caller functions forget to decrease the refcount of "smmu" increased by arm_smmu_rpm_get(), causing a refcount leak. Fix this issue by calling pm_runtime_resume_and_get() instead of pm_runtime_get_sync() in arm_smmu_rpm_get(), which can keep the refcount balanced in case of failure.

NLnet Labs Unbound w wersji 1.25.0 i wcześniejszych zawiera lukę w logice jostle, która mogła uniemożliwić jej prawidłowe działanie i pogorszyć wydajność rozwiązywania zapytań. Ponowne transmisje tego samego zapytania mogły przedłużyć wiek powoli działających zapytań, uniemożliwiając logice jostle rozpoznanie ich jako "stare" i potencjalne cele do zastąpienia nowymi zapytaniami. Osoba atakująca mogąca wysyłać zapytania do podatnego Unbound i kontrolująca serwer nazw domeny odpowiadający powoli i/lub złośliwie mogła wykorzystać tę lukę do degradacji wydajności rozwiązywania w Unbound. Po osiągnięciu limitu 'num-queries-per-thread', logika jostle się aktywuje. Gdy pojawi się nowe zapytanie, połowa dostępnych i powoli działających zapytań może być zastąpiona. Luka pojawia się, ponieważ zduplikowane zapytania wymagające rozwiązania zniekształcałyby wynik starz

Tor before 0.4.9.11 is prone to a use-after-free (and potential double free) of a conflux object when a recovery leg revives a conflux set whose last linked leg has already been closed. A malicious exit node could use this to crash a client. This is TROVE-2026-026.

An issue was discovered in the Linux Kernel from 4.18 to 4.19, an improper update of sock reference in TCP pacing can lead to memory/netns leak, which can be used by remote clients.

A flaw was found in grub2. When failing to mount an HFS+ grub, the hfsplus filesystem driver doesn't properly set an ERRNO value. This issue may lead to a NULL pointer access.

A flaw was found in the Linux kernel's netdevsim device driver, within the scheduling of events. This issue results from the improper management of a reference count. This may allow an attacker to create a denial of service condition on the system.

It was discovered that aufs improperly managed inode reference counts in the vfsub_dentry_open() method. A local attacker could use this vulnerability to cause a denial of service attack.

A vulnerability was identified in Mullvad wireguard.sys 0.10.1. The affected element is the function AdapterState of the component IOCTL Handler. Such manipulation leads to improper update of reference count. Local access is required to approach this attack. The exploit is publicly available and might be used. The vendor was contacted early about this disclosure.