Homepage

Use of Uninitialized Resource Affecting perf6.12-debuginfo package, versions <1:6.12.88-119.157.amzn2023

Severity

 Recommended
0.0
high
0
10

Based on Amazon Linux security rating.

Threat Intelligence

EPSS
0.13% (3rd percentile)

Do your applications use this vulnerable package?

In a few clicks we can analyze your entire application and see what components are vulnerable in your application, and suggest you quick fixes.

Test your applications
  • Snyk IDSNYK-AMZN2023-PERF612DEBUGINFO-17412005
  • published23 Jun 2026
  • disclosed28 May 2026
Report a new vulnerability Found a mistake?

Introduced: 28 May 2026

CVE-2026-46132  (opens in a new tab)
CWE-908  (opens in a new tab)

How to fix?

Upgrade Amazon-Linux:2023 perf6.12-debuginfo to version 1:6.12.88-119.157.amzn2023 or higher.
This issue was patched in ALAS2023-2026-1753.

NVD Description

Note: Versions mentioned in the description apply only to the upstream perf6.12-debuginfo package and not the perf6.12-debuginfo package as distributed by Amazon-Linux. See How to fix? for Amazon-Linux:2023 relevant fixed versions and status.

In the Linux kernel, the following vulnerability has been resolved:

net: rtnetlink: zero ifla_vf_broadcast to avoid stack infoleak in rtnl_fill_vfinfo

rtnl_fill_vfinfo() declares struct ifla_vf_broadcast on the stack without initialisation:

struct ifla_vf_broadcast vf_broadcast;

The struct contains a single fixed 32-byte field:

/* include/uapi/linux/if_link.h */
struct ifla_vf_broadcast {
    __u8 broadcast[32];
};

The function then copies dev->broadcast into it using dev->addr_len as the length:

memcpy(vf_broadcast.broadcast, dev-&gt;broadcast, dev-&gt;addr_len);

On Ethernet devices (the overwhelming majority of SR-IOV NICs) dev->addr_len is 6, so only the first 6 bytes of broadcast[] are written. The remaining 26 bytes retain whatever was previously on the kernel stack. The full struct is then handed to userspace via:

nla_put(skb, IFLA_VF_BROADCAST,
    sizeof(vf_broadcast), &amp;vf_broadcast)

leaking up to 26 bytes of uninitialised kernel stack per VF per RTM_GETLINK request, repeatable.

The other vf_* structs in the same function are explicitly zeroed for exactly this reason - see the memset() calls for ivi, vf_vlan_info, node_guid and port_guid a few lines above. vf_broadcast was simply missed when it was added.

Reachability: any unprivileged local process can open AF_NETLINK / NETLINK_ROUTE without capabilities and send RTM_GETLINK with an IFLA_EXT_MASK attribute carrying RTEXT_FILTER_VF. The kernel walks each VF and emits IFLA_VF_BROADCAST, leaking 26 bytes of stack per VF per request. Stack residue at this call site can include return addresses and transient sensitive data; KASAN with stack instrumentation, or KMSAN, will flag the nla_put() when reproduced.

Zero the on-stack struct before the partial memcpy, matching the existing pattern used for the other vf_* structs in the same function.

CVSS Base Scores

version 3.1