Guzzle up to 7.12.2 CookieJar SetCookie::matchesDomain session fixiation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$0-$5k0.00+

Summaryinfo

A vulnerability identified as critical has been detected in Guzzle up to 7.12.2. This affects the function SetCookie::matchesDomain of the component CookieJar. Performing a manipulation results in session fixiation. This vulnerability is reported as CVE-2026-59883. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability was found in Guzzle up to 7.12.2. It has been classified as critical. This affects the function SetCookie::matchesDomain of the component CookieJar. The manipulation with an unknown input leads to a session fixiation vulnerability. CWE is classifying the issue as CWE-384. Authenticating a user, or otherwise establishing a new user session, without invalidating any existing session identifier gives an attacker the opportunity to steal authenticated sessions. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Guzzle is an extensible PHP HTTP client. Prior to 7.12.3, CookieJar did not restrict cookies scoped to IP-address or bare-numeric Domain values to the exact host that set them, because SetCookie::matchesDomain() applied ordinary suffix matching to domains such as 192.168.0.1, [::1], or 1, allowing cross-host cookie disclosure, cookie injection, or session fixation. This issue is fixed in version 7.12.3.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-59883 since 07/07/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available.

Upgrading to version 7.12.3 eliminates this vulnerability.

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Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

Class: Session fixiation
CWE: CWE-384
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Upgrade: Guzzle 7.12.3

Timelineinfo

07/07/2026 CVE reserved
07/08/2026 +1 days Advisory disclosed
07/08/2026 +0 days VulDB entry created
07/08/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-59883 (🔒)
GCVE (CVE): GCVE-0-2026-59883
GCVE (VulDB): GCVE-100-376917

Entryinfo

Created: 07/08/2026 18:31
Changes: 07/08/2026 18:31 (53)
Complete: 🔍
Cache ID: 216::103

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