Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-101303— IPv6 UDP sendto(2) bypasses jail loopback restriction

Quick assessment

Affected
FreeBSD FreeBSD
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

在 IPv6 UDP 的未连接套接字发送路径中，未应用将回环目的地址重写为监狱（jail）主 IPv6 地址的 jail 策略。 在经典（非 VNET）jail 中的进程可以向监听于主机 IPv6 回环地址的服务发送 UDP 数据报，从而绕过 jail 的网络隔离机制。

AI Predicted 7.8 Difficulty: Moderate EPSS 0.19% · P8

Possible ATT&CK Techniques 1 AI

T1562

Affected Version Matrix 4

VendorProduct Version RangeStatus
FreeBSD FreeBSD 15.1-RELEASE< p4 affected
15.0-RELEASE< p14 affected
14.5-RELEASE< p1 affected
14.4-RELEASE< p10 affected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-101303

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
IPv6 UDP sendto(2) bypasses jail loopback restriction
Source: CVE Program / CVE List V5
Vulnerability Description
The IPv6 UDP send path for unconnected sockets did not apply the jail policy of rewriting a loopback destination address to the jail's primary IPv6 address. A process in a classic (non-VNET) jail can send UDP datagrams to services listening on the host's IPv6 loopback address, bypassing jail network isolation.
Source: CVE Program / CVE List V5
CVSS Information
N/A
Source: CVE Program / CVE List V5
Vulnerability Type
通信信道中错误指定的目的地
Source: CVE Program / CVE List V5

Affected Products

Vendor Product Affected Versions CPE Subscribe
FreeBSD FreeBSD 15.1-RELEASE ~ p4 -

II. Public POCs for CVE-2026-101303

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-101303

请登录查看更多情报信息。

Other References for CVE-2026-101303 (1)

Same Patch Batch · FreeBSD · 2026-10-15 · 13 CVEs total

CVE-2026-58099 Memory safety bugs in kqueue copy-on-fork implementation
CVE-2026-58098 Heap out-of-bounds access in semop(2)
CVE-2026-58100 Memory safety bugs in kqueue copy-on-fork implementation
CVE-2026-101302 Remote DoS via receive-side kernel TLS
CVE-2026-101306 Multiple jail filesystem root escapes
CVE-2026-101305 Multiple jail filesystem root escapes
CVE-2026-101304 Multiple jail filesystem root escapes
CVE-2026-101307 Remotely triggerable buffer overflow in tcp_rack
CVE-2026-101308 TOCTOU race between sound(4) buffer resizing and mmap
CVE-2026-101311 Multiple vulnerabilities in bhyve device models
CVE-2026-101309 Multiple vulnerabilities in bhyve device models
CVE-2026-101310 Multiple vulnerabilities in bhyve device models

IV. Related Vulnerabilities

Same product: FreeBSD
Same vendor: FreeBSD
Same weakness: CWE-941

V. Comments for CVE-2026-101303

No comments yet

Leave a comment