curl up to 8.21.0 SASL Negotiation communication channel to intended endpoints

Summaryinfo

A vulnerability identified as critical has been detected in curl. The affected element is an unknown function of the component SASL Negotiation. Performing a manipulation results in communication channel to intended endpoints. This vulnerability is identified as CVE-2026-13608. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in curl. It has been classified as critical. This affects some unknown functionality of the component SASL Negotiation. The manipulation with an unknown input leads to a communication channel to intended endpoints vulnerability. CWE is classifying the issue as CWE-923. The product establishes a communication channel to (or from) an endpoint for privileged or protected operations, but it does not properly ensure that it is communicating with the correct endpoint. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

A flaw in the libcurl SASL negotiation for LDAP authentication allows an incomplete handshake sequence to be misinterpreted as a successful cryptographic verification. An attacker executing a Man-in-the-Middle (MITM) attack can inject a premature or shortcut response that bypasses complete peer validation.

It is possible to read the advisory at curl.se. This vulnerability is uniquely identified as CVE-2026-13608 since 06/29/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/06/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-72164). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

• Network Utility Software

Name

• curl

Version

• 7.0
• 7.1
• 7.2
• 7.3
• 7.4
• 7.5
• 7.6
• 7.7
• 7.8
• 7.9
• 7.10
• 7.11
• 7.12
• 7.13
• 7.14
• 7.15
• 7.16
• 7.17
• 7.18
• 7.19
• 7.20
• 7.21
• 7.22
• 7.23
• 7.24
• 7.25
• 7.26
• 7.27
• 7.28
• 7.29
• 7.30
• 7.31
• 7.32
• 7.33
• 7.34
• 7.35
• 7.36
• 7.37
• 7.38
• 7.39
• 7.40
• 7.41
• 7.42
• 7.43
• 7.44
• 7.45
• 7.46
• 7.47
• 7.48
• 7.49
• 7.50
• 7.51
• 7.52
• 7.53
• 7.54
• 7.55
• 7.56
• 7.57
• 7.58
• 7.59
• 7.60
• 7.61
• 7.62
• 7.63
• 7.64
• 7.65
• 7.66
• 7.67
• 7.68
• 7.69
• 7.70
• 7.71
• 7.72
• 7.73
• 7.74
• 7.75
• 7.76
• 7.77
• 7.78
• 7.79
• 7.80
• 7.81
• 7.82
• 7.82.0
• 7.83
• 7.83.0
• 7.83.1
• 7.84
• 7.84.0
• 7.85
• 7.85.0
• 7.86
• 7.86.0
• 7.87
• 7.87.0
• 7.88.0
• 7.88.1
• 8.0
• 8.0.0
• 8.0.1
• 8.1
• 8.1.0
• 8.1.1
• 8.1.2
• 8.2
• 8.2.0
• 8.2.1
• 8.3
• 8.3.0
• 8.4
• 8.4.0
• 8.5
• 8.5.0
• 8.6
• 8.6.0
• 8.7
• 8.7.0
• 8.7.1
• 8.8
• 8.8.0
• 8.9
• 8.9.0
• 8.9.1
• 8.10
• 8.10.0
• 8.10.1
• 8.11
• 8.11.0
• 8.11.1
• 8.12
• 8.12.0
• 8.12.1
• 8.13
• 8.13.0
• 8.14
• 8.14.0
• 8.14.1
• 8.15
• 8.15.0
• 8.16
• 8.16.0
• 8.17
• 8.17.0
• 8.18
• 8.18.0
• 8.19
• 8.19.0
• 8.20
• 8.20.0
• 8.21.0

License

• open-source

CPE 2.3info

• 🔒
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CPE 2.2info

• 🔒
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Entryinfo

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