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No exploitation reportedFix available

CVE-2026-101307

Remotely triggerable buffer overflow in tcp_rack

No exploitation reported by the sources we read.

  • Published2026-10-15
  • WeaknessCWE-122 · CWE-787

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

When the PCM sample array needs to grow, the RACK stack doubles a 16-bit allocation counter. Repeated doublings caused the counter to wrap to zero, resulting in a near-zero-length allocation followed by a copy of the existing samples into the undersized buffer. A remote peer can trigger the expansion by sending a sufficient number of ACKs on an established connection. A remote attacker who can establish a TCP connection to a system using the RACK stack can trigger an out-of-bounds write of approximately 512 KB in the kernel heap possibly resulting in a kernel panic.

Timeline

dates in UTC
  1. 2026-10-1507:17CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-101307?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-101307?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD
Freebsd
BranchAffectedFixed in
15.1= 15.1no fix published

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof-of-concept repositories
none listed
PoC-in-GitHub

Sources

  • CISA-ADPSSVC decisionnone2026-10-15
  • OpenCVESSVC decisionnone—
  • CISA-ADPCVSS 4.08.22026-10-15
  • NVDCVSS 3.19.1read 2026-10-23
  • CNAweakness (CWE)CWE-122, CWE-787read 2026-10-23
  • FIRST EPSSEPSS score0.3 %2026-10-23

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
CVSS 4.0 vector
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Published
2026-10-15
Last Modified
2026-10-20
NVD status
Analyzed

Frequently asked questions

What is CVE-2026-101307?

When the PCM sample array needs to grow, the RACK stack doubles a 16-bit allocation counter. Repeated doublings caused the counter to wrap to zero, resulting in a near-zero-length allocation followed by a copy of the existing samples into the undersized buffer. A remote peer can trigger the expansion by sending a sufficient number of ACKs on an established connection. A remote attacker who can establish a TCP connection to a system using the RACK stack can trigger an out-of-bounds write of approximately 512 KB in the kernel heap possibly resulting in a kernel panic.

Is CVE-2026-101307 actively exploited?

Active exploitation of CVE-2026-101307 has not been confirmed. Its EPSS score was 0.3% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-101307?

CVE-2026-101307 has a CVSS v3 base score of 9.1 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H.

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