VulnerabilityPublished 18 Oct 2026

CVE-2026-98591: Linux kernel · bpf: Fix bounds check for skb-backed dynptrs

Source GCVE Database

Authoritative record:CVE-2026-98591· High

Not known to be exploited · fixed in ed6eec97b534979dcf28b40c389cee57bd6561d4 : patch Linux kernel soon.

Data as of 26 Oct 2026, 17:16 UTC

Severity

High

Rated by Threat Radar · CVSS not yet scored by NVD

EPSS: 0.2% chance of exploitation in 30 days – higher than 9% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in ed6eec97b534979dcf28b40c389cee57bd6561d4, 1196903a27cac5c929c7517e987a8d159f20c5e5, 37877a24758068742fef687a7cf5362360dde1d1 +2

Exploitation evidence

Disclosed: evidence found.
CVE published 18 Oct 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.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

ghsa-4j29-hvp6-5v88

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ 6f5a630d7c57cd79b1f526a95e757311e32d41e5, < ed6eec97b534979dcf28b40c389cee57bd6561d4	Fixed in ed6eec97b534979dcf28b40c389cee57bd6561d4
LinuxLinux	Affected ≥ 6f5a630d7c57cd79b1f526a95e757311e32d41e5, < 1196903a27cac5c929c7517e987a8d159f20c5e5	Fixed in 1196903a27cac5c929c7517e987a8d159f20c5e5
LinuxLinux	Affected ≥ 6f5a630d7c57cd79b1f526a95e757311e32d41e5, < 37877a24758068742fef687a7cf5362360dde1d1	Fixed in 37877a24758068742fef687a7cf5362360dde1d1
LinuxLinux	Affected ≥ 6f5a630d7c57cd79b1f526a95e757311e32d41e5, < 39ffceaddb10753eac12785dba6ac0673860b4ac	Fixed in 39ffceaddb10753eac12785dba6ac0673860b4ac
LinuxLinux	Affected ≥ 6f5a630d7c57cd79b1f526a95e757311e32d41e5, < 1b923538598be768e9f2f258a77a083d00e0c78b	Fixed in 1b923538598be768e9f2f258a77a083d00e0c78b
LinuxLinux	Affected =6.6	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 for this vulnerability has been implemented in the Linux kernel. Users should apply the official kernel updates that include this patch. Since this is a kernel-level issue, updating to a patched kernel version is the recommended remediation.

Description

A vulnerability in the Linux kernel's skb_pointer_if_linear() function caused an unsigned integer underflow in bounds checking for skb-backed BPF dynptrs. This underflow led to incorrect pointer calculations, potentially backing dynamic pointers with invalid memory. The issue has been resolved by preventing underflow and overflow in the arithmetic checks.

References

Community reviews

Loading reviews…