CVE-2026-66339

mediumpriority · track · 0EPSS 0.002 · 16 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.25% (16th) EPSS

CVSS 6.5 · medium

Is it mine?

6 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-28

A flaw was found in libsoup. After a CONNECT tunnel is established through an HTTP proxy, libsoup incorrectly attaches the Proxy-Authorization header to subsequent HTTPS requests sent through that tunnel to the destination server. This allows the destination server to capture proxy credentials, leading to information disclosure.

cvss

Technical severity, 0–10. One row per scoring source.

6.5

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:Nsecondary · ENISA EU

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:Nsecondary · secalert@redhat.com USexploitability 2.8 · impact 3.6

v3.16mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-201US

affected products (6)

Products and version ranges known to be affected.

gnome libsoupall versionsnvdUScpe:2.3:a:gnome:libsoup:*:*:*:*:*:*:*:*
redhat enterprise linux= 10.0nvdUScpe:2.3:o:redhat:enterprise_linux:*:*:*:*:*:*:*:*
redhat enterprise linux= 6.0nvdUScpe:2.3:o:redhat:enterprise_linux:*:*:*:*:*:*:*:*
redhat enterprise linux= 7.0nvdUScpe:2.3:o:redhat:enterprise_linux:*:*:*:*:*:*:*:*
redhat enterprise linux= 8.0nvdUScpe:2.3:o:redhat:enterprise_linux:*:*:*:*:*:*:*:*
redhat enterprise linux= 9.0nvdUScpe:2.3:o:redhat:enterprise_linux:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2026-07-24modified 2026-08-24

references (6)

External citations — patches, advisories, analysis.

https://access.redhat.com/security/cve/CVE-2026-66339 cnnvd
https://bugzilla.redhat.com/show_bug.cgi?id=2506951 cnnvd
https://access.redhat.com/security/cve/CVE-2026-66339 enisa_euvd
https://bugzilla.redhat.com/show_bug.cgi?id=2506951 enisa_euvd
https://access.redhat.com/security/cve/CVE-2026-66339Vendor Advisorynvd
https://bugzilla.redhat.com/show_bug.cgi?id=2506951Issue TrackingVendor AdvisoryExploitMitigationnvd

scry

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