curl up to 8.21.0 SASL Negotiation communication channel to intended endpoints

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.3$0-$5k0.00

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 09/13/2026).

The vulnerability scanner Nessus provides a plugin with the ID 343957 (openSUSE 16: curl / curl-fish-completion / curl-zsh-completion / libcurl-devel / etc (openSUSE-SU-2026:21774-1)), which helps to determine the existence of the flaw in a target environment.

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 databases at CNNVD (CNNVD-2026-96920039), Tenable (343957) and EUVD (EUVD-2026-72164). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.3
VulDB Meta Temp Score: 7.3

VulDB Base Score: 7.3
VulDB Temp Score: 7.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

ADP CISA Base Score: 7.4
ADP CISA Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Communication channel to intended endpoints
CWE: CWE-923
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 343957
Nessus Name: openSUSE 16: curl / curl-fish-completion / curl-zsh-completion / libcurl-devel / etc (openSUSE-SU-2026:21774-1)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

06/29/2026 CVE reserved
09/06/2026 +69 days Advisory disclosed
09/06/2026 +0 days VulDB entry created
09/13/2026 +7 days VulDB entry last update

Sourcesinfo

Advisory: curl.se
Status: Confirmed

CVE: CVE-2026-13608 (🔒)
GCVE (CVE): GCVE-0-2026-13608
GCVE (VulDB): GCVE-100-399471
EUVD: 🔒
CNNVD: CNNVD-2026-96920039 - curl 授权问题漏洞

Entryinfo

Created: 09/06/2026 20:09
Updated: 09/13/2026 12:06
Changes: 09/06/2026 20:09 (52), 09/06/2026 21:45 (1), 09/08/2026 01:26 (6), 09/09/2026 16:38 (2), 09/13/2026 12:06 (9)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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