Access of Uninitialized Pointer Affecting perf6.18-debuginfo package, versions <1:6.18.25-52.107.amzn2023


Severity

Recommended
high

Based on Amazon Linux security rating.

Threat Intelligence

EPSS
0.12% (3rd percentile)

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  • Snyk IDSNYK-AMZN2023-PERF618DEBUGINFO-17287206
  • published10 Jun 2026
  • disclosed1 May 2026

Introduced: 1 May 2026

CVE-2026-43036  (opens in a new tab)
CWE-824  (opens in a new tab)

How to fix?

Upgrade Amazon-Linux:2023 perf6.18-debuginfo to version 1:6.18.25-52.107.amzn2023 or higher.
This issue was patched in ALAS2023-2026-1746.

NVD Description

Note: Versions mentioned in the description apply only to the upstream perf6.18-debuginfo package and not the perf6.18-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: use skb_header_pointer() for TCPv4 GSO frag_off check

Syzbot reported a KMSAN uninit-value warning in gso_features_check() called from netif_skb_features() [1].

gso_features_check() reads iph->frag_off to decide whether to clear mangleid_features. Accessing the IPv4 header via ip_hdr()/inner_ip_hdr() can rely on skb header offsets that are not always safe for direct dereference on packets injected from PF_PACKET paths.

Use skb_header_pointer() for the TCPv4 frag_off check so the header read is robust whether data is already linear or needs copying.

[1] https://syzkaller.appspot.com/bug?extid=1543a7d954d9c6d00407

CVSS Base Scores

version 3.1