Is CVE-2006-4434 in the CISA KEV catalog?

No. CVE-2006-4434 is not currently on the CISA Known Exploited Vulnerabilities list.

What is the CVSS severity of CVE-2006-4434?

CVE-2006-4434 has a CVSS v3 base score of 7.5 (HIGH).

What is the EPSS score for CVE-2006-4434?

CVE-2006-4434 has an EPSS score of 4.33% (90th percentile), estimating the probability of exploitation in the next 30 days.

How do I fix CVE-2006-4434?

Upgrade sendmail on debian 11 to 8.13.8-1 or later.

CVE & CISA-KEV Catalog

CVE-2006-4434

HIGHEPSS 90th pctl

7.5

CVSS v3

NVD

Description

Use-after-free vulnerability in Sendmail before 8.13.8 allows remote attackers to cause a denial of service (crash) via a long "header line", which causes a previously freed variable to be referenced. NOTE: the original developer has disputed the severity of this issue, saying "The only denial of service that is possible here is to fill up the disk with core dumps if the OS actually generates different core dumps (which is unlikely)... the bug is in the shutdown code (finis()) which leads directly to exit(3), i.e., the process would terminate anyway, no mail delivery or receiption is affected."

CWE-416Use After Free

How to fix

Remediation Available

sendmailDebian

Fixed in:8.13.8-1CVE-2006-4434

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

Impact

ConfidentialityNone

IntegrityNone

AvailabilityHigh

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Exploit Intelligence

4.33%probability of exploitation in 30 days

90thpercentile

High risk: more likely to be exploited than 90% of all known CVEs.

References

Patch4

Vendor Advisory6

Third-Party Advisory1

openbsd.org

Mailing List1

attrition.org

Release Notes2

Other references5

Related Vulnerabilities

Other CWE-416 (Use After Free) vulnerabilities, ordered by exploit likelihood. View all

CVE	Severity	CVSS	EPSS	Exploited	Fix
CVE-2019-0708	Critical	9.8	100%	KEV + Ransom	-
CVE-2021-31166	Critical	9.8	100%	KEV	Fix
CVE-2015-5119	Critical	9.8	99%	KEV	-
CVE-2010-3962	High	8.1	97%	KEV	-
CVE-2015-0313	Critical	9.8	96%	KEV	Fix
CVE-2017-9798	High	7.5	95%	-	Fix

Embed a live status badge for CVE-2006-4434

Markdown

[![CVE-2006-4434](https://tridentstack.com/cve/badge/CVE-2006-4434.svg)](https://tridentstack.com/cve/CVE-2006-4434)

HTML

<a href="https://tridentstack.com/cve/CVE-2006-4434"><img src="https://tridentstack.com/cve/badge/CVE-2006-4434.svg" alt="CVE-2006-4434"></a>

Find and fix vulnerabilities across your fleet

TridentStack Control continuously scans your Windows, macOS, and Linux fleet for known vulnerabilities, prioritizes them by severity and active exploitation, and patches them automatically.

Start free

This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-04-16.