CVE-2026-98158: Linux kernel · ppp_async: drop the errored frame instead of resetting its headroom
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 5.5 High.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 1% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 25 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A fix is available that changes the error handling in ppp_async to drop errored frames instead of resetting skb headroom, preventing the kernel panic and out-of-bounds read. Users should apply the official Linux kernel patches that address this issue. No additional mitigation is required once the patch is applied.
Description
A vulnerability in the Linux kernel's PPP asynchronous driver (ppp_async) could cause a kernel panic or out-of-bounds read due to improper handling of skb headroom when processing errored frames. The issue arises because the errored frame handling resets skb headroom incorrectly, violating the NET_SKB_PAD guarantee and leading to memory corruption. The vulnerability can be triggered remotely by a peer sending crafted frames, resulting in a denial-of-service (DoS) condition. A patch has been applied to drop errored frames instead of resetting headroom, preventing the kernel panic and out-of-bounds read.
References
- ubuntu.com/security/CVE-2026-98158 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-98158 (opens in a new tab)
- git.kernel.org/stable/c/0c53eb14975f029abd6b26896a460f0d2aaefe6b (opens in a new tab)
- git.kernel.org/stable/c/717137221c7d90e7c98bda9a370c9da6cbf015e5 (opens in a new tab)
- git.kernel.org/stable/c/d0fc3dabfe67caf084e7119ceb2ee23f5ad2f2da (opens in a new tab)
- git.kernel.org/stable/c/8dc5d98a16fa23c00999aecf10018c9f69fa5bf4 (opens in a new tab)
- nvd.nist.gov/vuln/detail/CVE-2026-98158 (opens in a new tab)
- git.kernel.org/stable/c/25f354c55b8435d1f51b8a0a05a3cfe429358523 (opens in a new tab)
- git.kernel.org/stable/c/a86a17745c3e1c6fadd4d6e90c03552dfe531c8c (opens in a new tab)
- git.kernel.org/stable/c/c4bb894362d224b699e2f95c6c26707d9654e4a3 (opens in a new tab)
- git.kernel.org/stable/c/ff035780adb0f49dc2c7ada26b4697849a68bec8 (opens in a new tab)