HomeCVE Intelligence › CVE-2026-31431
CVSS 8.0 HIGH 🔴 ACTIVELY EXPLOITED Vulnerability

CVE-2026-31431: Copy Fail exploit lets 732 bytes hijack Linux systems and quietly grab root

<!-SC_OFF --><div class="md"><p>This new Linux kernel bug called Copy Fail (CVE-2026-31431) is kinda terrifying because it’s not complicated at all. A normal user can run a tiny 732-byte scri…

8.0CVSS Score
HIGHSeverity
NOCISA KEV
VulnerabilityImpact Type

📋 Vulnerability Details

CVE IDCVE-2026-31431
Vendorreddit_netsec
Affected ProductThreat Intelligence
Vulnerability TypeVulnerability
CVSS Score8.0 (HIGH)
Actively Exploited✅ Yes
Patch StatusSee Vendor Advisory →
Reported ByCYBERDUDEBIVASH SENTINEL APEX Intelligence (via reddit_netsec)

🔬 Technical Analysis

<!-- SC_OFF --><div class="md"><p>This new Linux kernel bug called Copy Fail (CVE-2026-31431) is kinda terrifying because it’s not complicated at all. A normal user can run a tiny 732-byte script and get root, no race conditions or luck required, and it works across major distros like Ubuntu, RHEL, and SUSE. The exploit quietly modifies the page cache instead of the file on disk, so integrity checks don’t catch it, but the kernel still executes the tampered version in memory.</p> <p>Even worse, since the page cache is shared, it can potentially cross container boundaries too. Patch ASAP if your distro hasn’t already, because this one feels way too reliable…</p> </div><!-- SC_ON -->   submitted by   <a href="h

🎯 Known Indicators of Compromise

{"type":"url","value":"https://www.reddit.com/user/OkReport5065">","confidence_score":0.82,"first_seen":"2026-05-01","source_count":1} {"type":"url","value":"https://nerds.xyz/2026/04/copy-fail-linux-root-exploit/">[link]</a></span>","confidence_score":0.82,"first_seen":"2026-05-01","source_count":1} {"type":"url","value":"https://www.reddit.com/r/netsec/comments/1szduu3/copy_fail_exploit_lets_732_bytes_hijack_linux/&quot","confidence_score":0.82,"first_seen":"2026-05-01","source_count":1} {"type":"domain","value":"www.reddit.com","confidence_score":0.75,"first_seen":"2026-05-01","source_count":1} {"type":"domain","value":"nerds.xyz","confidence_score":0.75,"first_seen":"2026-05-01","source_count":1}

📚 Advisory References

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