CVE Tools
Track your stack

CVE-2023-51765

Public exploit available. Not confirmed exploited in the wild yet. Fixed versions are out.

CVSS 3.15.3MediumEPSS percentile65th1.1% chance in 30 daysCISA KEVNot listedNo confirmed exploitation
Public exploit: 1 sourceFix5 products2 fixed builds listed below
Check it yourself

OpenVAS · 10 checks

e.g. OID 1.3.6.1.4.1.25623.1.0.114256

Run the check

Published Updated Sources: CVE.org, NVD, BDU

NVD CVE.org

What to do

Find your product and version, then upgrade to the build on the right.

  • SendmailAffected: < 8.18.0.2Upgrade to: 8.18.0.2Stated by: NVD
  • FreebsdAffected: < 11.0Upgrade to: 11.0Stated by: NVD
  • Red Hat Inc. Red Hat Enterprise LinuxAffected: 8.0Upgrade to: not statedStated by: BDU
  • ООО «Ред Софт» РЕД ОСAffected: 7.3Upgrade to: not statedStated by: BDU
  • Sendmail Inc. SendMail SMTP ServerAffected: до 8.18.0.2Upgrade to: not statedStated by: BDU

Versions as the sources state them. Full version matrix after sign-in

Check it yourselfA free OpenVAS check exists for this CVE. Run it against your hosts.Is your organisation exposed?Request an assessment to establish which checks fit your systems.

What it is

From the CVE record

sendmail through 8.17.2 allows SMTP smuggling in certain configurations. Remote attackers can use a published exploitation technique to inject e-mail messages with a spoofed MAIL FROM address, allowing bypass of an SPF protection mechanism. This occurs because sendmail supports <LF>.<CR><LF> but some other popular e-mail servers do not. This is resolved in 8.18 and later versions with 'o' in srv_features.

In plain language

No plain-language summary for this CVE yet.

Exploitation

Where each signal puts this CVE on the scale from published to confirmed exploited.

EPSS65th
Public exploit
CISA KEV

Not in the catalog. CISA has not confirmed exploitation.

Public exploits

1 source with a proof of concept or module.

Exploit links, PoCs and Metasploit modules after sign-in
EPSS

1.1% chance of exploitation activity in the next 30 days, which ranks it in the 65th percentile of scored CVEs.

Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.

Lifecycle

The patch came 471 days before any public exploit.

  1. OpenVAS check added
  2. Public exploit / PoCsource: other
  3. Patch availablerecord updated
  4. Publishedweakness classified, att&ck mapped

Affected products

And 2 more affected products. See all after sign-in

Technical detail

CVSS 3.1 vector

Open in the CVSS calculator

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

Scored 5.3 by NVD.

How it is reached

  • Attack Vector NetworkExploitable remotely over the network without any special conditions
  • Attack Complexity LowNo special conditions — the attack can be reliably reproduced
  • Privileges Required NoneNo authentication required — anyone can exploit this
  • User Interaction NoneNo user interaction needed — fully automated exploitation

Scope

  • Scope UnchangedImpact is limited to the vulnerable component itself

Impact if exploited

  • Confidentiality NoneNo confidentiality impact
  • Integrity LowData modification is possible but limited in scope or consequence
  • Availability NoneNo availability impact

Weaknesses

ATT&CK techniques

Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.

Sources

References in the record

And 17 more references. See all after sign-in

Watch the software you run.

My Stack ranks new CVEs for your products by real-world exploitation, so the next serious one reaches you without reading every advisory.

We'll flag the next CVE, public exploit or patch for Sendmail, not every advisory. This one: public exploit.