LiveActive security incident?Get immediate response
CVE Record

CVE-2024-36927: ipv4: Fix uninit-value access in __ip_make_skb()

In the Linux kernel, the following vulnerability has been resolved: ipv4: Fix uninit-value access in __ip_make_skb() KMSAN reported uninit-value access in __ip_make_skb() [1]. __ip_make_skb() tests HDRINCL to know if the skb has icmphdr. However, HDRINCL can cause a race condition. If calling setsockopt(2) with IP_HDRINCL changes HDRINCL while __ip_make_skb() is running, the function will access icmphdr in the skb even if it is not included. This causes the issue reported by KMSAN. Check FLOWI_FLAG_KNOWN_NH on fl4->flowi4_flags instead of testing HDRINCL on the socket. Also, fl4->fl4_icmp_type and fl4->fl4_icmp_code are not initialized. These are union in struct flowi4 and are implicitly initialized by flowi4_init_output(), but we should not rely on specific union layout. Initialize these explicitly in raw_sendmsg(). [1] BUG: KMSAN: uninit-value in __ip_make_skb+0x2b74/0x2d20 net/ipv4/ip_output.c:1481 __ip_make_skb+0x2b74/0x2d20 net/ipv4/ip_output.c:1481 ip_finish_skb include/net/ip.h:243 [inline] ip_push_pending_frames+0x4c/0x5c0 net/ipv4/ip_output.c:1508 raw_sendmsg+0x2381/0x2690 net/ipv4/raw.c:654 inet_sendmsg+0x27b/0x2a0 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x274/0x3c0 net/socket.c:745 __sys_sendto+0x62c/0x7b0 net/socket.c:2191 __do_sys_sendto net/socket.c:2203 [inline] __se_sys_sendto net/socket.c:2199 [inline] __x64_sys_sendto+0x130/0x200 net/socket.c:2199 do_syscall_64+0xd8/0x1f0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 Uninit was created at: slab_post_alloc_hook mm/slub.c:3804 [inline] slab_alloc_node mm/slub.c:3845 [inline] kmem_cache_alloc_node+0x5f6/0xc50 mm/slub.c:3888 kmalloc_reserve+0x13c/0x4a0 net/core/skbuff.c:577 __alloc_skb+0x35a/0x7c0 net/core/skbuff.c:668 alloc_skb include/linux/skbuff.h:1318 [inline] __ip_append_data+0x49ab/0x68c0 net/ipv4/ip_output.c:1128 ip_append_data+0x1e7/0x260 net/ipv4/ip_output.c:1365 raw_sendmsg+0x22b1/0x2690 net/ipv4/raw.c:648 inet_sendmsg+0x27b/0x2a0 net/ipv4/af_inet.c:851 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x274/0x3c0 net/socket.c:745 __sys_sendto+0x62c/0x7b0 net/socket.c:2191 __do_sys_sendto net/socket.c:2203 [inline] __se_sys_sendto net/socket.c:2199 [inline] __x64_sys_sendto+0x130/0x200 net/socket.c:2199 do_syscall_64+0xd8/0x1f0 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6d/0x75 CPU: 1 PID: 15709 Comm: syz-executor.7 Not tainted 6.8.0-11567-gb3603fcb79b1 #25 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-1.fc39 04/01/2014

UnknownCVSS not scoredNot KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

CVE-2024-36927 is a Linux kernel IPv4 bug found by memory-safety testing. A race around IP_HDRINCL can make the kernel read uninitialized packet data. The bundle does not show real-world exploitation, a CVSS score, or business impact beyond affected Linux kernel exposure.

Executive priority

Treat this as a normal kernel maintenance item unless vendor guidance raises severity for a specific product. There is no KEV listing or cited active exploitation, but broad Linux estate exposure makes timely patch validation appropriate.

Technical view

In __ip_make_skb(), the kernel checked socket HDRINCL state while send processing could race with setsockopt(IP_HDRINCL). That could make it inspect an ICMP header not present in the skb. The fix uses flowi4 flags and explicitly initializes ICMP type and code in raw_sendmsg().

Likely exposure

Exposure is likely limited to Linux systems running affected kernel builds or vendor kernels that have not backported the stable fix. Confirm against your distribution, appliance, and embedded Linux advisories rather than relying only on upstream version numbers.

Exploitation context

The source bundle cites a KMSAN/syzkaller-style report and kernel stable fixes. It marks KEV as false and provides no cited evidence of active exploitation or public weaponization. Practical exploitability and impact are not established in the provided sources.

Researcher notes

The record is sparse: no CVSS, CWE, or concrete exploit impact is supplied. The key technical artifact is the race between HDRINCL state and __ip_make_skb() header assumptions, plus missing explicit initialization of flowi4 ICMP fields.

Mitigation direction

  • Update Linux kernels through the relevant distribution or vendor channel.
  • Confirm the update includes the cited upstream stable kernel fixes.
  • Follow Debian LTS guidance where Debian LTS systems are in scope.
  • Follow Siemens SSA-019113 for affected Siemens products.
  • If no vendor advisory exists, request vendor confirmation of backport status.

Validation and detection

  • Inventory Linux kernel versions across servers, appliances, containers hosts, and embedded systems.
  • Map each kernel to vendor advisories or the upstream stable fix references.
  • Check package changelogs for CVE-2024-36927 or the referenced kernel commits.
  • Prioritize systems that run untrusted local workloads or expose multi-tenant execution.
  • Record exceptions where vendors state the kernel is unaffected or already backported.
Prepared
Confidence
medium
Sources
10

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cve · low confidence lookup

CVE-2024-36927 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
3Timeline events
3ADP providers
9Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: noneAutomatable: noTechnical Impact: partial

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. CVE publishedCVE Program

    The CVE record was published.

  3. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CISA-ADPCISA ADP Vulnrichment
other:ssvc
CVECVE Program Container
siemens-SADPADP container

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
LinuxLinux566785731c6dd41ef815196ddc36d1ae30a63763, a54ec573d9b81b05d368f8e6edc1b3e49f688658, fc60067260c20da8cddcf968bec47416f3e2cde2, 99e5acae193e369b71217efe6f1dad42f3f18815, 99e5acae193e369b71217efe6f1dad42f3f18815, 99e5acae193e369b71217efe6f1dad42f3f18815, dc4e3bb0710178c8d03fc43064e0a71fe7440cdd, 022ea4374c319690c804706bda9dc42946d1556d, 27c468ec1af113f6ae94fb5378f65e6038bd16e7, 32a5a13d556e4f804e5a447a08c70b172d600707, 9e3c96aed8fe32907e0a4bca05aad457629a820c, 5.10.180, 5.15.111, 6.1.28, 4.14.315, 4.19.283, 5.4.243, 6.2.15, 6.3.2unaffected
LinuxLinux6.4, 0, 5.10.248, 5.15.198, 6.1.140, 6.6.31, 6.8.10, 6.9affected
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.