VulnerabilityPublished 1 Jun 2026Updated 2 Jun 2026

CVE-2026-49267: Apache Airflow · Improper Certificate Validation

Affects Apache AirflowSource CVE Database V5

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Mentioned vulnerabilities

CVE-2026-41016

Not known to be exploited · CVSS 5.9 Medium : upgrade to 3.2.2 when convenient.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 3.1 base score

5.9Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.1% chance of exploitation in 30 days – higher than 8% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 3.2.2

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

Attack Vector: Network
Attack Complexity: High
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: None
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: High: A successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected. For example, a successful attack may require an attacker to: gather knowledge about the environment in which the vulnerable target/component exists; prepare the target environment to improve exploit reliability; or inject themselves into the logical network path between the target and the resource requested by the victim in order to read and/or modify network communications (e.g., a man in the middle attack).
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 1 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade Apache Airflow to 3.2.2.

Affected software

Product	Affected	Fixed in
Apache Software FoundationApache Airflow	Affected >=2.0.0 <3.2.2	Fixed in 3.2.2
PyPIapache-airflow`pkg:pypi/apache-airflow`Other threats	Affected =2.0.0	Fixed in–

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Users should upgrade Apache Airflow to version 3.2.2 or later, which addresses this improper certificate validation issue in the core airflow.utils.email code path. Additionally, users who have applied the fix for the related SMTP provider vulnerability (CVE-2026-41016) should ensure their core Airflow version is also updated to 3.2.2 or later. There is no indication that temporary workarounds or configuration changes fully mitigate this issue without upgrading. Patch status is not explicitly confirmed in the advisory, but the vendor recommends upgrading to 3.2.2 or later as the remediation.

Description

Apache Airflow versions configured with smtp_starttls=True and smtp_ssl=False establish SMTP STARTTLS connections without verifying the remote server's certificate. This improper certificate validation allows a network man-in-the-middle attacker to present a self-signed certificate, causing the worker to complete the TLS handshake silently and potentially expose SMTP authentication credentials and email contents. The vulnerability affects Apache Airflow core prior to version 3.2.2 and is related to a previously addressed issue in the SMTP provider component. Users should upgrade to Apache Airflow 3.2.2 or later to mitigate this risk.

Impact

An attacker able to intercept network traffic between the Airflow worker and the SMTP server can present a fraudulent certificate during the STARTTLS handshake. Because the certificate is not validated, the attacker can decrypt SMTP authentication credentials and email message contents sent by the worker. This compromises confidentiality of email data and credentials, potentially allowing further unauthorized access or data leakage. The vulnerability requires a network man-in-the-middle position and affects deployments where the SMTP relay is outside the worker's trust boundary and configured with smtp_starttls=True and smtp_ssl=False.

CWE-295Improper Certificate Validation (opens in a new tab)
Base weaknessOWASP Top 10 A07:2025: Authentication Failures (opens in a new tab)
The product does not validate, or incorrectly validates, a certificate.
Architecture and Design · Implementation
Certificates should be carefully managed and checked to assure that data are encrypted with the intended owner's public key.
Implementation
If certificate pinning is being used, ensure that all relevant properties of the certificate are fully validated before the certificate is pinned, including the hostname.
OWASP Cheat Sheets
Transport Layer Protection (opens in a new tab)
TLS Cipher String (opens in a new tab)
OWASP Authentication (opens in a new tab)
OWASP ASVS 4.0.3
V9.2.1 (opens in a new tab)
V1.9.2 (opens in a new tab)
V2.8.5 (opens in a new tab)
Attack patterns
Creating a Rogue Certification Authority Certificate (opens in a new tab)
Signature Spoofing by Improper Validation (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 10 Jul 2026, 09:49 UTC

WeaknessesCWE-295

Technical details

References

Community reviews

Related threats