VulnerabilityPublished 25 Jul 2026Updated 19 Aug 2026

CVE-2026-64508: Linux kernel · bpf: Support for hardening against JIT spraying

Affects Linux kernelSource GCVE Database

Compare

Not known to be exploited.

Data as of 3 Nov 2026, 18:44 UTC

Severity

Medium

Rated Medium by Threat Radar's AI analysis · No CVSS score from NVD or the CNA

Thin evidence

One scorer or none

Exploitation evidence

Disclosed: evidence found.
CVE published 25 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 3 Nov 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.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), 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.

What to do

AI-suggested

A fix has been implemented in the Linux kernel that flushes indirect branch predictors before reusing JIT memory in the BPF JIT allocator. Users should apply the updated kernel versions containing this fix once available. No additional mitigation actions are specified or required beyond applying the official fix.

Description

A vulnerability in the Linux kernel's BPF JIT allocator has been addressed by adding support for hardening against JIT spraying attacks. The issue arises because the allocator reuses executable memory space for multiple small programs, which can lead to indirect branch predictions from previous programs being reused, potentially enabling an attacker to bypass security mechanisms. The fix involves flushing indirect branch predictors before reusing JIT memory to prevent reuse of stale predictions. This mitigation is implemented via a static key and call that architectures can update as needed. Larger allocations are not flushed but are considered safe due to program size constraints.

Impact

This vulnerability could allow an attacker to exploit branch prediction reuse in the BPF JIT allocator to facilitate JIT spraying attacks, potentially bypassing security mechanisms that rely on indirect branch prediction. The fix reduces this risk by flushing branch predictors before reusing JIT memory, thereby preventing reuse of stale predictions. No known exploits in the wild have been reported.

Summary

The Linux kernel's BPF JIT allocator packs multiple small programs into larger executable memory allocations and reuses this space as programs are loaded and freed. This reuse can cause indirect jumps into newly written programs to reuse branch predictions left by previous programs occupying the same memory, which can be exploited for JIT spraying attacks. The vulnerability is mitigated by flushing indirect branch predictors before reusing JIT memory, implemented through a static key and call mechanism allowing architecture-specific flush functions. Allocations larger than a pack are not flushed but are considered safe due to size constraints on unprivileged programs. A warning is issued if assumptions about program size are violated while the flush is active.

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 3 Nov 2026, 18:44 UTC

Technical details

References

Community reviews

Related threats