CVE-2026-5265Disclosure

LOWCVSS 6.5 · MEDIUM

Signal is active with 1 mentions in latest observed window

Immediate actions

Patch affected systems immediately

Recommended action window: Monitor and triage in normal cycle

NVD description

When generating an ICMP Destination Unreachable or Packet Too Big response, the handler copies a portion of the original packet into the ICMP error body using the IP header's self-declared total length (ip_tot_len for IPv4, ip6_plen for IPv6) without validating it against the actual packet buffer size. A VM can send a short packet with an inflated IP length field that triggers an ICMP error (e.g., by hitting a reject ACL), causing ovn-controller to read heap memory beyond the valid packet data and include it in the ICMP response sent back to the VM.

Back to dashboard

0.5/ 10 priority

Sources & remediation

Other references

Weakness type (CWE)

CWE-130

Priority

LOW

Exploitation

NONE

PoC

NONE

Patch

AVAILABLE

Momentum

STABLE

Threat summary

Patch or workaround signal is available
4 mentions across 4 observed days
Momentum state: stable

What's happening

Patch or workaround mentioned in 1 signal
Technical details provided in 3 signals
Disclosure: 2 classified signals
General: 1 classified signal
Peaked 3d ago at 1 mentions (2026-04-20); latest day: 1
4 total mentions across 4 days

Deep dive

Activity timeline4 mentions / 4d

Signal classification3 categories

Disclosure

250.0%

General

125.0%

Patch

125.0%

Referenced assets5 URLs

By indicator

Classification over time

Date	Total	Labels

2026-04-20	1	Disclosure1
2026-04-21	1	General1
2026-04-23	1	Patch1
2026-04-25	1	Disclosure1

Full discourse4 posts

Open Source Security mailing list@oss_security171d
Disclosure
OVN (Open Virtual Network) CVE-2026-5265: Heap Over-Read in ICMP Error Response Generation https://www.openwall.com/lists/oss-security/2026/04/20/4 CVE-2026-5367: Heap over-read in DHCPv6 Client ID processing https://www.openwall.com/lists/oss-security/2026/04/20/5
Post summary
The post announces two heap over‑read vulnerabilities in Open Virtual Network (CVE‑2026‑5265 and CVE‑2026‑5367) with concise technical descriptions, but no exploits, patches, or active exploitation reports.
02092613
4.7K followersView on X
Misbar | مسبار@MisbarSec168d
Patch
📌 تنبيه أمان OVN: ثغرات خطيرة في القراءة الزائدة من الذاكرة Heap تعرض البيانات الحساسة للتسرب أصدر فريق الشبكة الافتراضية المفتوحة (OVN) تحذيرًا أمنيًا بشأن ثغرتين خطيرتين في القراءة الزائدة من الذاكرة Heap، وهما CVE-2026-5265 و CVE-2026-5367. يمكن أن تؤدي هذه الثغرات إلى تسرب البيانات الحساسة. يوصى بتحديث الأنظمة المتضررة وتفعيل إجراءات الأمان اللازمة. — يُنصح بتحديث البرامج ومراجعة الإعدادات الأمنية. 🔗 للمزيد: https://securityonline.info/ovn-heap-over-read-packet-leakage-advisory/
Post summary
The advisory announces critical heap over‑read vulnerabilities (CVE-2026-5265/5367) and urges users to apply patches and review security settings.
00030900
268 followersView on X
CVE@CVEnew166d
Disclosure
CVE-2026-5265 When generating an ICMP Destination Unreachable or Packet Too Big response, the handler copies a portion of the original packet into the ICMP error body using the IP he… https://www.cve.org/CVERecord?id=CVE-2026-5265
Post summary
The text describes the technical details of CVE-2026-5265, highlighting improper copying of packet data during ICMP error response generation.
0000087
57.2K followersView on X
Vulmon Vulnerability Feed@VulmonFeeds170d
General
CVE-2026-5265 Re https://vulmon.com/vulnerabilitydetails?qid=CVE-2026-5265
Post summary
The message simply references CVE-2026-5265 and links to a Vulmon page for further details, offering no additional information on exploitation, patches, or technical specifics.
0000023
4.0K followersView on X

Explore more

Back to dashboard

What researchers are saying

CVE-2026-5265

Misbar | مسبار[verified]@MisbarSecPatch

The advisory announces critical heap over‑read vulnerabilities (CVE-2026-5265/5367) and urges users to apply patches and review security settings.

Open Source Security mailing list@oss_securityDisclosure

The post announces two heap over‑read vulnerabilities in Open Virtual Network (CVE‑2026‑5265 and CVE‑2026‑5367) with concise technical descriptions, but no exploits, patches, or active exploitation reports.

CVE@CVEnewDisclosure

The text describes the technical details of CVE-2026-5265, highlighting improper copying of packet data during ICMP error response generation.

Vulmon Vulnerability Feed@VulmonFeedsGeneral

The message simply references CVE-2026-5265 and links to a Vulmon page for further details, offering no additional information on exploitation, patches, or technical specifics.