Vulmon
Amazon Linux 2 Security Advisory: ALASLIVEPATCH-2023-155
Advisory Release Date: 2023-10-31 00:16 Pacific
Advisory Updated Date: 2023-11-01 00:48 Pacific
FAQs regarding Amazon Linux ALAS/CVE Severity
A use-after-free vulnerability in the Linux kernel's netfilter: nf_tables component can be exploited to achieve local privilege escalation.
When nf_tables_delrule() is flushing table rules, it is not checked whether the chain is bound and the chain's owner rule can also release the objects in certain circumstances.
We recommend upgrading past commit 6eaf41e87a223ae6f8e7a28d6e78384ad7e407f8. (CVE-2023-3777)
A use-after-free flaw was found in the Linux kernel's netfilter in the way a user triggers the nft_pipapo_remove function with the element, without a NFT_SET_EXT_KEY_END. This issue could allow a local user to crash the system or potentially escalate their privileges on the system. (CVE-2023-4004)
netfilter: nf_tables: disallow rule addition to bound chain via NFTA_RULE_CHAIN_ID (CVE-2023-4147)
A use-after-free vulnerability in the Linux kernel's net/sched: cls_route component can be exploited to achieve local privilege escalation.
When route4_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free.
We recommend upgrading past commit b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8. (CVE-2023-4206)
A use-after-free vulnerability in the Linux kernel's net/sched: cls_fw component can be exploited to achieve local privilege escalation.
When fw_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free.
We recommend upgrading past commit 76e42ae831991c828cffa8c37736ebfb831ad5ec. (CVE-2023-4207)
A use-after-free vulnerability in the Linux kernel's net/sched: cls_u32 component can be exploited to achieve local privilege escalation.
When u32_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free.
We recommend upgrading past commit 3044b16e7c6fe5d24b1cdbcf1bd0a9d92d1ebd81. (CVE-2023-4208)
A use-after-free vulnerability in the Linux kernel's af_unix component can be exploited to achieve local privilege escalation.
The unix_stream_sendpage() function tries to add data to the last skb in the peer's recv queue without locking the queue. Thus there is a race where unix_stream_sendpage() could access an skb locklessly that is being released by garbage collection, resulting in use-after-free.
We recommend upgrading past commit 790c2f9d15b594350ae9bca7b236f2b1859de02c. (CVE-2023-4622)
A use-after-free vulnerability in the Linux kernel's net/sched: sch_hfsc (HFSC qdisc traffic control) component can be exploited to achieve local privilege escalation.
If a class with a link-sharing curve (i.e. with the HFSC_FSC flag set) has a parent without a link-sharing curve, then init_vf() will call vttree_insert() on the parent, but vttree_remove() will be skipped in update_vf(). This leaves a dangling pointer that can cause a use-after-free.
We recommend upgrading past commit b3d26c5702c7d6c45456326e56d2ccf3f103e60f. (CVE-2023-4623)
A use-after-free vulnerability in the Linux kernel's net/sched: sch_qfq component can be exploited to achieve local privilege escalation.
When the plug qdisc is used as a class of the qfq qdisc, sending network packets triggers use-after-free in qfq_dequeue() due to the incorrect .peek handler of sch_plug and lack of error checking in agg_dequeue().
We recommend upgrading past commit 8fc134fee27f2263988ae38920bc03da416b03d8. (CVE-2023-4921)
Affected Packages:
kernel-livepatch-5.10.186-179.751
Issue Correction:
Please ensure you have live patching enabled.
Run yum update kernel-livepatch-5.10.186-179.751 to update your system.
aarch64:
kernel-livepatch-5.10.186-179.751-1.0-1.amzn2.aarch64
kernel-livepatch-5.10.186-179.751-debuginfo-1.0-1.amzn2.aarch64
src:
kernel-livepatch-5.10.186-179.751-1.0-1.amzn2.src
x86_64:
kernel-livepatch-5.10.186-179.751-1.0-1.amzn2.x86_64
kernel-livepatch-5.10.186-179.751-debuginfo-1.0-1.amzn2.x86_64