CyberSecBulletin
CVE-2026-98096NVD status: Analyzed

Linux: Out-of-bounds Write

Published Updated By the CyberSecBulletin desk

CVE-2026-98096 is a high-severity out-of-bounds write vulnerability in Linux, with a CVSS 3.1 base score of 7.4 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions f463c4786cf27376de7dfc0833a12e924a98f698, 8f44d4160bcdb3136a9145a4b9c7816382976925, 9cfbe2c381ab6d00a08e7a5b6028865adfb4e1bc as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.51% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Linux to f463c4786cf27376de7dfc0833a12e924a98f698 or 8f44d4160bcdb3136a9145a4b9c7816382976925 or 9cfbe2c381ab6d00a08e7a5b6028865adfb4e1bc or af08f62b5a5a446d6134a92d86771d3d12e0e3da, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.10.271 or 5.15.222 or 6.1.189 or 6.6.158, whichever matches your release line, or a later version.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux1ababeba4a21f3dba3da3523c670b207fb2feb62 up to, but not including, f463c4786cf27376de7dfc0833a12e924a98f698; 1ababeba4a21f3dba3da3523c670b207fb2feb62 up to, but not including, 8f44d4160bcdb3136a9145a4b9c7816382976925; 1ababeba4a21f3dba3da3523c670b207fb2feb62 up to, but not including, 9cfbe2c381ab6d00a08e7a5b6028865adfb4e1bc; 1ababeba4a21f3dba3da3523c670b207fb2feb62 up to, but not including, af08f62b5a5a446d6134a92d86771d3d12e0e3da; 1ababeba4a21f3dba3da3523c670b207fb2feb62 up to, but not including, ce4c8beedc19aceeab0e7bdc6f34394fb158c47c; 1ababeba4a21f3dba3da3523c670b207fb2feb62 up to, but not including, 97b21ef57dfabbff660a4672c9fef7edfb720f47; 1ababeba4a21f3dba3da3523c670b207fb2feb62 up to, but not including, 3ad7dca5e03bd64c65983a19734337512fd75491; 1ababeba4a21f3dba3da3523c670b207fb2feb62 up to, but not including, 975b5b067f525a1b1338c4a3bee1c46545801518; and 1 more rangesf463c4786cf27376de7dfc0833a12e924a98f698, 8f44d4160bcdb3136a9145a4b9c7816382976925, 9cfbe2c381ab6d00a08e7a5b6028865adfb4e1bc, af08f62b5a5a446d6134a92d86771d3d12e0e3da, ce4c8beedc19aceeab0e7bdc6f34394fb158c47c, 97b21ef57dfabbff660a4672c9fef7edfb720f47
LinuxLinux Kernel4.10 up to, but not including, 5.10.271; 5.11 up to, but not including, 5.15.222; 6.0 up to, but not including, 6.1.189; 6.2 up to, but not including, 6.6.158; 6.7 up to, but not including, 6.12.111; 6.13 up to, but not including, 6.18.53; 6.19 up to, but not including, 7.2.7; 7.35.10.271, 5.15.222, 6.1.189, 6.6.158, 6.12.111, 6.18.53

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
HighSuccess depends on conditions outside the attacker's control.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:H. Scored by CNA.

Official description

In the Linux kernel, the following vulnerability has been resolved: ipv6: sr: restore network header before routing and forwarding ipv6_srh_rcv() runs with skb->data at the Segment Routing Header (SRH) while skb_network_header() points at the IPv6 header. When segments_left > 0, ipv6_srh_rcv() previously restored the skb->data position by pushing sizeof(struct ipv6hdr), assuming the SRH immediately followed the fixed IPv6 header. If another extension header (such as a Hop-by-Hop options header) precedes the SRH, skb_network_offset() remained negative. This led to two problems: 1. During ip6_route_input(), fib6_rules_early_flow_dissect() invokes __skb_flow_dissect() which passes the negative skb_network_offset() to flow dissection, breaking BPF and C flow dissector logic. 2. If forwarded via ip6_forward() or redirected via act_mirred, downstream handlers (like sch_fragment() or neighbour output) pass the negative offset as an unsigned length, triggering OOB memcpy or buffer overflows. Fix this by pushing -skb_network_offset(skb) before routing, ensuring skb_network_offset(skb) is 0 for route lookup / flow dissection as well as downstream forwarding. On the loopback path, pull skb_transport_offset(skb) to restore skb->data to the SRH before looping back.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Out-of-bounds Write

The product writes data past the end, or before the beginning, of the intended buffer.

How developers prevent this class of flaw

  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer. Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples include the Safe C String Library (SafeStr) by Messier and Viega, and the Strsafe.h library from Microsoft. These libraries provide safer versions of overflow-prone string-handling functions.
  • Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking. D3-SFCV (Stack Frame Canary Validation) from D3FEND discusses canary-based detection in detail.

More Out-of-bounds Write vulnerabilities (CWE-787)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Recent Out-of-bounds Write vulnerabilities

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