CVE-2022-49340 Affecting kernel-debug-core package, versions <0:5.14.0-162.6.1.el9_1


Severity

Recommended
0.0
medium
0
10

Based on Red Hat Enterprise Linux security rating.

Threat Intelligence

EPSS
0.1% (29th 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-RHEL9-KERNELDEBUGCORE-10316139
  • published6 Jun 2025
  • disclosed26 Feb 2025

Introduced: 26 Feb 2025

CVE-2022-49340  (opens in a new tab)

How to fix?

Upgrade RHEL:9 kernel-debug-core to version 0:5.14.0-162.6.1.el9_1 or higher.
This issue was patched in RHSA-2022:8267.

NVD Description

Note: Versions mentioned in the description apply only to the upstream kernel-debug-core package and not the kernel-debug-core package as distributed by RHEL. See How to fix? for RHEL:9 relevant fixed versions and status.

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

ip_gre: test csum_start instead of transport header

GRE with TUNNEL_CSUM will apply local checksum offload on CHECKSUM_PARTIAL packets.

ipgre_xmit must validate csum_start after an optional skb_pull, else lco_csum may trigger an overflow. The original check was

if (csum &amp;&amp; skb_checksum_start(skb) &lt; skb-&gt;data)
    return -EINVAL;

This had false positives when skb_checksum_start is undefined: when ip_summed is not CHECKSUM_PARTIAL. A discussed refinement was straightforward

if (csum &amp;&amp; skb-&gt;ip_summed == CHECKSUM_PARTIAL &amp;&amp;
    skb_checksum_start(skb) &lt; skb-&gt;data)
    return -EINVAL;

But was eventually revised more thoroughly:

  • restrict the check to the only branch where needed, in an uncommon GRE path that uses header_ops and calls skb_pull.
  • test skb_transport_header, which is set along with csum_start in skb_partial_csum_set in the normal header_ops datapath.

Turns out skbs can arrive in this branch without the transport header set, e.g., through BPF redirection.

Revise the check back to check csum_start directly, and only if CHECKSUM_PARTIAL. Do leave the check in the updated location. Check field regardless of whether TUNNEL_CSUM is configured.

CVSS Base Scores

version 3.1